Update #1: Severe Warnings were issued for these storms around 2030Z
Update #2: No severe reports across WY were in as of 0045Z
- Jack Swigert
Showing posts with label Convective Initiation. Show all posts
Showing posts with label Convective Initiation. Show all posts
Thursday, May 10, 2018
CI Low but Severe CI High?
Today's CI products seemed to pinpoint the initial convection for the day the best so far this week across SE Wyoming. However, CI was highlighting convection potential at 30-40% but Severe CI was highlighting areas 80-90% off convective clouds off Snowy Range and Laramie Mountains. Why would it only be a low chance of convective initiation but a higher chance of severe convection?
Update #1: Severe Warnings were issued for these storms around 2030Z
Update #2: No severe reports across WY were in as of 0045Z
- Jack Swigert
Update #1: Severe Warnings were issued for these storms around 2030Z
Update #2: No severe reports across WY were in as of 0045Z
- Jack Swigert
Thursday, May 3, 2018
GLM and Convective Inititation
Saw an interesting example of a developing CB (over land at the Haiti/Dominican Republic border) where GLM flashed before development was recognizable on satellite.
First, a longer loop. Then a shorter loop focused on three frames. All data is time matched to satellite. In addition to GLM, ENI is plotted on the upper left (small yellow dots).
At the center of each of the four images is the developing cell. The first flash occurs on frame 4 of 12. It's most noticeable on the lower right with VIS and Total Energy. Then, notice on the upper right the enhanced IR. The flash seemed to practically come from nowhere, but then the cloud becomes more recognizably convective a couple frames later.
Satellite times above are 2012-2017-2022Z, with the initial flash at 2017Z. Again, notice the upper right enhanced IR with little to see. Max tops estimated by cloud top temp in the sequence was FL280-FL320 (flash)-FL350. The cloud top ended up a frame or two later peaking at FL380. ENI didn't pick this up for a few frames after this loop.
Sequence of GLM product values for the event:
Total Energy: 0fJ - 52 - 0.4
Flash Extent Density: 0 - 1 - 1
Event Density: 0 - 42 - 3
Area Extent. 0km^2 - 1122 - 70.2
Eric happened by while I was checking this out and made an interesting comment. The intense, single flash was likely seen very clearly from the satellite since the icing/charge must have been restricted to the cloud top. Thus, GLM can be useful for recognizing convective initiation.
-Forrest
First, a longer loop. Then a shorter loop focused on three frames. All data is time matched to satellite. In addition to GLM, ENI is plotted on the upper left (small yellow dots).
 |
| Satellite/Lightning 2002-2057Z |
At the center of each of the four images is the developing cell. The first flash occurs on frame 4 of 12. It's most noticeable on the lower right with VIS and Total Energy. Then, notice on the upper right the enhanced IR. The flash seemed to practically come from nowhere, but then the cloud becomes more recognizably convective a couple frames later.
 |
| Three framed loop. Initial flash is frame 2. |
Satellite times above are 2012-2017-2022Z, with the initial flash at 2017Z. Again, notice the upper right enhanced IR with little to see. Max tops estimated by cloud top temp in the sequence was FL280-FL320 (flash)-FL350. The cloud top ended up a frame or two later peaking at FL380. ENI didn't pick this up for a few frames after this loop.
Sequence of GLM product values for the event:
Total Energy: 0fJ - 52 - 0.4
Flash Extent Density: 0 - 1 - 1
Event Density: 0 - 42 - 3
Area Extent. 0km^2 - 1122 - 70.2
Eric happened by while I was checking this out and made an interesting comment. The intense, single flash was likely seen very clearly from the satellite since the icing/charge must have been restricted to the cloud top. Thus, GLM can be useful for recognizing convective initiation.
-Forrest
Monday, May 4, 2015
Day 1 Initial Set-up
Well, the first post of day 1 and I have to admit I feel a bit overwhelmed with the amount of information and data to look at as we are supposed to look at all the available experimental products as we assess the environment for the day and also build procedures for the rest of the week. I think I will feel a bit more comfortable when we are focused a bit more and looking at specific products within the warning operations environment.
Initial look at the big picture shows a deep trough over the desert southwest with somewhat diffluent flow across the southern plains with downstream ridging over the Mississippi Valley.
A surface frontal boundary was noted across north central KS with possible weak low lifting northeastward through southeast NE. Some weak convergence resulting in developing convection across northeast KS as of 19z. Best instability at 19z based on the GOES-R LAP algorithm was centered over western OK into southern KS and expanding into the southern part of Topeka's Forecast Area, which seemed reasonable when compared to the RAP13 analysis at 19z. There has been little if any lightning in the convection over northeast KS to this point so have not evaluated the lightning data too much.
An initial look at the convection initiation algorithm off the GOES-R over northeast KS did not reveal much with generally less than 20 % initiation values leading up to the convection that has developed. There is a fairly dense layer of cirrus overhead which is likely obscuring the ability of the GOES-R to detect and leading to the low percentages, which is a limiting factor of this product.
Jack Bauer
A surface frontal boundary was noted across north central KS with possible weak low lifting northeastward through southeast NE. Some weak convergence resulting in developing convection across northeast KS as of 19z. Best instability at 19z based on the GOES-R LAP algorithm was centered over western OK into southern KS and expanding into the southern part of Topeka's Forecast Area, which seemed reasonable when compared to the RAP13 analysis at 19z. There has been little if any lightning in the convection over northeast KS to this point so have not evaluated the lightning data too much.
An initial look at the convection initiation algorithm off the GOES-R over northeast KS did not reveal much with generally less than 20 % initiation values leading up to the convection that has developed. There is a fairly dense layer of cirrus overhead which is likely obscuring the ability of the GOES-R to detect and leading to the low percentages, which is a limiting factor of this product.
Jack Bauer
Tuesday, May 7, 2013
EWP2013 7 May 2013 2215 UTC Mesoscale Discussion
With multiple scans of CI/CTC showing iminent or ongoing convective initiation over Lubbock’s area, will localized one desk at the LUB wfo. This will give the testbed an opportunity to evaluate some of the PGLM products available in the LUB LMA. The image below from 2145 UTC shows where storms are developing in extreme south central parts of the CWA.
Radar trends show activity is also on the uptick at DDC, with ongoing supercells over GLD’s area. Will keep two teams stationed at these locations to optimize this marginal severe weather setup. The image below is a four panel of MESH products and composite reflectivity over the DDC and GLD CWAs.
Will continue to monitor trends, but all areas appear to be covered at this time.
Austin
Austin
Following GOES-R CI
I had the chance to follow-up with forecaster Hatzos on the use of the GOES-R CI from a couple posts earlier. The operations were watching the Goodland and Dodge City, Kansas county warning areas as we continued to wait for storms to possibly fire up in eastern Colorado / western Kansas. We had the chance to discuss how the GOES-R CI product was performing given the current environment.
The image above is from 2015 UTC shows the GOES-R CI (upper left), IR imagery (upper right), and the Dodge City reflectivity (lower right). Looking at the previous observations, the GOES-R CI has done a good job of identifying the small cells developing in western Kansas, as shown in the radar imagery.
The image above is now from 2030 UTC and continues to show GOES-R CI identifying initiation with moderate values. I posed the question of what is the impression of these observations. Overall, the GOES-R CI has done well identifying initiation. In addition, the GOES-R CI values have been modest. During the conversation, this gave the forecaster the opinion that explosive development is not to be expected just yet and that given the current conditions, the operations will focus on monitoring storm development.
- Geoffrey
The image above is from 2015 UTC shows the GOES-R CI (upper left), IR imagery (upper right), and the Dodge City reflectivity (lower right). Looking at the previous observations, the GOES-R CI has done a good job of identifying the small cells developing in western Kansas, as shown in the radar imagery.
The image above is now from 2030 UTC and continues to show GOES-R CI identifying initiation with moderate values. I posed the question of what is the impression of these observations. Overall, the GOES-R CI has done well identifying initiation. In addition, the GOES-R CI values have been modest. During the conversation, this gave the forecaster the opinion that explosive development is not to be expected just yet and that given the current conditions, the operations will focus on monitoring storm development.
- Geoffrey
EWP daily debriefing 5/7
This afternoon we had our first EWP daily debrief from the previous day's activities. Yesterday the focus was on the mid-Atlantic coast, specifically the Blacksburg, VA CWA, and while forecasters did issue a handful of warnings, it was an overall quiet day. However, the more docile weather allowed them a chance to work through each set of new data, learning which products they have at their disposal and how to use them. Here are a few comments picked up throughout the day:
Simulated Imagery
- 'We used the simulated imagery to forecast the dissipation of storms in the evening.' This along with the Nearcasting indicated the dissipation of storms in the area of interest.
- 'The WRF simulated imagery seems to be more spotty; it doesn't often seem to forecast the broader cloud shields associated with storm systems.'
Nearcasting Model
- 'The theta-e difference showed stable air moving into the area' and along with the simulated imagery, was used in the forecasting of the dissipation of the storms.
- 'I liked the two and three hour forecasting'
GOES-R CI and Cloud Top Cooling
- Because of the more docile weather 'there were no 80/90% CI values so it made the product more difficult to use'
RGB Airmass
- 'It takes some time to intuitively understand exactly what you're looking at with this product and how it can be integrated into your forecasting techniques, but it has potential'
Training
- Forecasters completed a training shift previous to their arrival in Norman. Monday was then used as a low key forecasting day, giving them a chance to get familiar with the products in an operational setting
- 'Having a chance to interact and use the products on a less busy day was very helpful'
Stay tuned to the blog for further feedback and updates on daily activity!
Simulated Imagery
- 'We used the simulated imagery to forecast the dissipation of storms in the evening.' This along with the Nearcasting indicated the dissipation of storms in the area of interest.
- 'The WRF simulated imagery seems to be more spotty; it doesn't often seem to forecast the broader cloud shields associated with storm systems.'
Nearcasting Model
- 'The theta-e difference showed stable air moving into the area' and along with the simulated imagery, was used in the forecasting of the dissipation of the storms.
- 'I liked the two and three hour forecasting'
GOES-R CI and Cloud Top Cooling
- Because of the more docile weather 'there were no 80/90% CI values so it made the product more difficult to use'
RGB Airmass
- 'It takes some time to intuitively understand exactly what you're looking at with this product and how it can be integrated into your forecasting techniques, but it has potential'
Training
- Forecasters completed a training shift previous to their arrival in Norman. Monday was then used as a low key forecasting day, giving them a chance to get familiar with the products in an operational setting
- 'Having a chance to interact and use the products on a less busy day was very helpful'
Stay tuned to the blog for further feedback and updates on daily activity!
Friday, June 10, 2011
EWP end of week debrief... 10 June
Today marks the last day of the last week of the experiment. As is tradition, we debriefed the EWP visiting forecasters on their experiences throughout the week...
Convective Initiation
- (Thursday event - N.E.) Cloud-top cooling products seemed to work in diagnosing the strength of storms on the southwest edge of the line that were newly developing.
- Even though CI didn't always occur... false hits were useful in identifying clouds trying to break the cap.
- Forecasters not interested in seeing a binary yes/no output.
- "There were instances where similar looking clumps of Cu that one would flag for CI but the other wouldn't... so I wasn't sure how to interpret that other than maybe this area was more conducive to further development."
- There are lots of products that provide you lead time on CI, the real question would be on the consistency of the output.
- "I would definitely look at this in my WFO... especially the cooling-tops product gave me a lot of information on the relative strengths of the storms."
- "If both groups could work together and come up with a probabilistic product that combined the strengths of the UAH and the UWCI products, that would be very useful."
- "I think from a purely public forecast perspective, especially this time of year where we get convection every day, it would help you identify when exactly CI will occur."
- Would be very valuable for nocturnal CI.
Nearcast
- (Thursday event - N.E.) "I didn't see a whole lot of trend in terms of gradients developing, but all the sudden on the back side of the squall-line we lost data rapidly, probably due to cloud cover... compared to the other days, I didn't see any real patterns."
- (Thursday event - KS/OK) Showed an arch of destabilization between 2200-0300 across the eastern halves of OK and KS... storms formed on the western edge of this gradient and forecaster did not expect the storms to diminish anytime soon and thus increased warning confidence... stronger wording regarding hail/wind potential in warning was issued.
- There seemed to be small scale features in the fields, areas of relative maximum that were moving around... would be nice to compare to radar evolution and see how those areas affected the storm structure.
- Helped understand why convection occurred and where it would occur... definitely the 1-6 or 1-9 hour timeframe was the most useful aspect of it.
- Having a 4-panel set up of the individual layers in addition to the difference field to help increase the understanding of the product.
- The color-table in AWIPS was poor... Also, the values were reversed from those in NAWIPS and on the web. The individual layers of PW were also not available in AWIPS.
Would it be useful to extend the Nearcast another 3 hours, even if that meant smoother fields?
- "I like the high resolution out to whenever we can have it... it seemed that there was definitely information within the gradients... of course if you add 3 hours, we will definitely take that."
Would you have used the observations without it being advected forward?
- Wouldn't have been as useful... It helped determine the evolution of the environment... The forecast parts tended to build areas of increased instability that helped provide guidance on what was going to happen later on.
Overshooting-top / Thermal Couplet
- (Thursday event - KS/OK) None were detected when forecasters expected to see detections, so was not used, especially with the rapid updates of radar data.
- Need to remember to turn icon density to "MAX" within AWIPS or some detections will be lost.
- Looked at pretty much every day... for the most part, operator identified OTs occurred before the algorithm did.
Pseudo-GLM
- (Thursday event - OK) Some of the storms to the east had higher flash rates, but this was an artifact of the LMA network's detection efficiencies.
- (Thursday event - OK) Flash rates would pick up a short time before increases in reflectivity.
- Was useful for diagnosing lightning danger... get a lot of calls from the public regarding that within the WFO.
Overall
- Would definitely help to have some pre-configured procedures before forecasters arrived... forecasters used the "ultimate CI" procedure heavily and liked to see what we think they should be combining to help enhance the utility of the products. Forecasters can then adjust the color-scales for their own preferences.
- "I liked the morning/evening shift idea... that was nice... got to experience something different everyday."
- Sometimes the forecasters would get to tied into warning operations mode and forget to look at the experimental products... would be nice to make sure that the forecasters understand that there is no real pressure and to take their time to examine all of the experimental stuff.
- Would have been useful to provide the forecasters with the training via visitview prior to arrival, as well as some cases that the forecasters could use to get familiar with the products and decrease spin-up time... This would have to be done very far in advance.
- Interaction with the EFP CI desk was not done because there were so many participants over in the area.
- EFP/EWP daily briefing was seen to be repetitive between all the groups and not very "brief" as one forecaster stated. Also, the information being provided was more academic than pure weather discussion.
- WE NEED MORE CHAIRS!
Convective Initiation
- (Thursday event - N.E.) Cloud-top cooling products seemed to work in diagnosing the strength of storms on the southwest edge of the line that were newly developing.
- Even though CI didn't always occur... false hits were useful in identifying clouds trying to break the cap.
- Forecasters not interested in seeing a binary yes/no output.
- "There were instances where similar looking clumps of Cu that one would flag for CI but the other wouldn't... so I wasn't sure how to interpret that other than maybe this area was more conducive to further development."
- There are lots of products that provide you lead time on CI, the real question would be on the consistency of the output.
- "I would definitely look at this in my WFO... especially the cooling-tops product gave me a lot of information on the relative strengths of the storms."
- "If both groups could work together and come up with a probabilistic product that combined the strengths of the UAH and the UWCI products, that would be very useful."
- "I think from a purely public forecast perspective, especially this time of year where we get convection every day, it would help you identify when exactly CI will occur."
- Would be very valuable for nocturnal CI.
Nearcast
- (Thursday event - N.E.) "I didn't see a whole lot of trend in terms of gradients developing, but all the sudden on the back side of the squall-line we lost data rapidly, probably due to cloud cover... compared to the other days, I didn't see any real patterns."
- (Thursday event - KS/OK) Showed an arch of destabilization between 2200-0300 across the eastern halves of OK and KS... storms formed on the western edge of this gradient and forecaster did not expect the storms to diminish anytime soon and thus increased warning confidence... stronger wording regarding hail/wind potential in warning was issued.
- There seemed to be small scale features in the fields, areas of relative maximum that were moving around... would be nice to compare to radar evolution and see how those areas affected the storm structure.
- Helped understand why convection occurred and where it would occur... definitely the 1-6 or 1-9 hour timeframe was the most useful aspect of it.
- Having a 4-panel set up of the individual layers in addition to the difference field to help increase the understanding of the product.
- The color-table in AWIPS was poor... Also, the values were reversed from those in NAWIPS and on the web. The individual layers of PW were also not available in AWIPS.
Would it be useful to extend the Nearcast another 3 hours, even if that meant smoother fields?
- "I like the high resolution out to whenever we can have it... it seemed that there was definitely information within the gradients... of course if you add 3 hours, we will definitely take that."
Would you have used the observations without it being advected forward?
- Wouldn't have been as useful... It helped determine the evolution of the environment... The forecast parts tended to build areas of increased instability that helped provide guidance on what was going to happen later on.
Overshooting-top / Thermal Couplet
- (Thursday event - KS/OK) None were detected when forecasters expected to see detections, so was not used, especially with the rapid updates of radar data.
- Need to remember to turn icon density to "MAX" within AWIPS or some detections will be lost.
- Looked at pretty much every day... for the most part, operator identified OTs occurred before the algorithm did.
Pseudo-GLM
- (Thursday event - OK) Some of the storms to the east had higher flash rates, but this was an artifact of the LMA network's detection efficiencies.
- (Thursday event - OK) Flash rates would pick up a short time before increases in reflectivity.
- Was useful for diagnosing lightning danger... get a lot of calls from the public regarding that within the WFO.
Overall
- Would definitely help to have some pre-configured procedures before forecasters arrived... forecasters used the "ultimate CI" procedure heavily and liked to see what we think they should be combining to help enhance the utility of the products. Forecasters can then adjust the color-scales for their own preferences.
- "I liked the morning/evening shift idea... that was nice... got to experience something different everyday."
- Sometimes the forecasters would get to tied into warning operations mode and forget to look at the experimental products... would be nice to make sure that the forecasters understand that there is no real pressure and to take their time to examine all of the experimental stuff.
- Would have been useful to provide the forecasters with the training via visitview prior to arrival, as well as some cases that the forecasters could use to get familiar with the products and decrease spin-up time... This would have to be done very far in advance.
- Interaction with the EFP CI desk was not done because there were so many participants over in the area.
- EFP/EWP daily briefing was seen to be repetitive between all the groups and not very "brief" as one forecaster stated. Also, the information being provided was more academic than pure weather discussion.
- WE NEED MORE CHAIRS!
Thursday, June 9, 2011
Integrating CI information into a single situational awareness tool
Discussions with forecasters throughout this year's Spring Experiment have raised an interesting topic regarding how to supply information without overwhelming forecasters during forecast and warning operations. In particular, forecasters have expressed interest in looking at all of the background interest fields from the UAH SATCAST product, which is currently being used as a proxy for the GOES-R CI product. The official GOES-R CI product will have 12 interest fields, all with a unique piece of information about the growth of a cumulus cloud object. As defined within the current GOES-R Algorithm Working Group (AWG) requirements, the CI product will only provide the forecasters with a binary yes/no output. Currently being provided within AWIPS/NAWIPS during the Spring Experiment, SATCAST has 6 interest fields that determine whether or not a cloud object is expected to convectively initiate within the next 0-2 hour time-frame. Forecasters have expressed some displeasure with only being provided a yes/no field to help them determine whether CI will occur. Some ideas have been offered that include providing a probabilistic CI nowcast, similar to what UWCI provides, or providing them with all of the CI interest fields individually in addition to the yes/no nowcast. Providing the forecasters with all of the interest fields and expecting them to look at them within their AWIPS/NAWIPS display is not feasible as it will be extremely distracting and time consuming. The problem with providing a probabilistic approach is that you are removing the detailed information that the forecasters would like to see but currently do not have to time to look at. So what do we do?
An interesting solution to this problem arose during a car ride on the way to pick up dinner this evening during a break in EWP operations. Why not provide a display that looks similar to a binary yes/no product, but be able to (on mouse-over perhaps) interrogate all of the interest field information? Currently within AWIPS you are able to do this for a single field. For instance, you can display radar reflectivity and interrogate the actual dBZ value on mouse-over. What if it were possible to provide information from multiple fields on mouse-over in this similar manner while still providing a simple to understand one-size-fits-all display for the product? Some food for thought.
An interesting solution to this problem arose during a car ride on the way to pick up dinner this evening during a break in EWP operations. Why not provide a display that looks similar to a binary yes/no product, but be able to (on mouse-over perhaps) interrogate all of the interest field information? Currently within AWIPS you are able to do this for a single field. For instance, you can display radar reflectivity and interrogate the actual dBZ value on mouse-over. What if it were possible to provide information from multiple fields on mouse-over in this similar manner while still providing a simple to understand one-size-fits-all display for the product? Some food for thought.
Tuesday, May 31, 2011
UW CTC Highlights Most Rapid Development of Convective Line
The UW Cloud-Top Cooling (CTC) rate cannot only be used to nowcast convection initiation, but also highlight the most rapid vertical growth along a line of developing convective clouds. Below is the GOES visible imagery/UW CTC valid at 1732 UTC 31 May 2011 and base radar reflectivity at the same time. The entire line of towering cumulus over central Michigan looks similar on visible imagery, but the UW CTC highlights (green circle) the most rapidly growing and hence precipitating portion of the line (also green circle).
Wednesday, May 11, 2011
1.5 Hour Lead Time from UAH CI Algorithm
Figure 1.
UAH CI forecast (red) valid from the 2040 UTC GOES imagery.
Figure 2.
Radar valid at 2042 UTC.
Figure 3.
Radar valid at 2209 UTC.
The UAH CI algorithm forecasted CI (first instance of 35+dBZ radar echo) approximately 1.5 hours before it was detected on radar for this case in western Minnesota (Figures 1 - 3, above). As subsequent GOES imagery rolled in, the algorithm continued to forecast CI down along a line of growing clouds to the south, achieving lead times of around 1 hour. According to the Storm Prediction Center storm reports (see Figure 4, below), this line of storms quickly turned severe and went on to produce several instances of large hail and even a tornado!
Figure 4.
SPC storm reports for 05/10/2011, valid through ~12 UTC on 05/11/2011.
Innovative Methods for Displaying UAH CI Product in AWIPS
Some of the forecasters here in the Experimental Warning Program are finding creative ways to integrate the UAH CI product (GOES-R AWG CI product proxy) into their AWIPS workstations. Above is an excellent example of this. In the top-left display quadrant, the Null (blue) and Positive (red) cloud object CI forecasts are overlaid onto GOES Visible satellite data, with an option to change the transparency of the two integrated data sets at the touch of a button. Similarly, in the top-right display quadrant, the UAH CI product is overlaid onto radar data.... This way the forecasters will know where to focus their attention on the radar for future development, especially in regions where severe weather is expected but not yet initiated.
Tuesday, May 10, 2011
UAH CI (SATCAST) Now Up and Flowing...
Despite a few early glitches in the product delivery, the UAH CI product is now flowing into the SPC Hazardous Weather Testbed AWIPS and N-AWIPS workstations regularly. The posted pic (above) is the first image that was received for "real-time" display in this year's newly created Convective Initiation desk.
From the time of the first GOES scan line (the image time stamp), it took only 10 minutes for the data to be processed, delivered, and displayed..... This is a significant advantage over the time latency issues the UAH CI product had from last year (our first year of "real-time" processing and evaluation). This is typical for Northern Hemisphere scans from GOES. For pure CONUS scans from GOES, it generally only takes about 8 minutes to accomplish the same process. From the moment the GOES data is downloaded, it takes a mere ~1.5 - 2.5 minutes to process it and produce the CI output forecast.
Friday, June 18, 2010
EWP weekly debrief
Today is the end of this year's Spring Experiment, and what a fitting end. Yesterday was our busiest day in the EWP over ND/MN/IA. As of the time of this entry there were 65 tornadoes reported over the area associated with the event. It was indeed a big day, and luckily there were no technical issues during the IOP. Unfortunately, due to the rapid developing nature of this event the GOES-R products were used only for a short time before it was essential to move into radar operations for warning purposes. The forecasters were inundated with issuing tornado warning pretty much in a consistent line from Canada down into IA. We were able to get some feedback and since this is the weekly debrief I was able to ask the forecasters in more detail, based on my observations this week as well as their survey responses. Here is a breakdown of what we discussed...
UWCI
I asked about the lead times from the surveys... 15-30 mins the general consensus?
"Hard to be sure because we were arriving at the HWT after convection was developing."
"Getting in there around noon would get more accurate results."
"The case event was already initiated when I got there."
"Struggling giving up screen space during severe weather" (from survey)... is there a display you think would help?
"Having an additional head would help. We were only provided with two screens so it changed our strategy."
"Would be useful for the mesoanalyst position at the WFO."
"4-panel devoted to those products works well."
I asked the forecasters if they were ok with more signals if that meant giving up some FAR...
"I would like earlier signals, like a probability signal... which part of my CWA is going to have the best chance... Some kind of signal before there's aggitated clouds would be helpful."
I asked the forecasters whether they preferred the CI or the cloud-top cooling...
"I used them both... kind of liked them both simultaneously."
"It was hard because it seemed it was 50/50 on detecting things so I lost a lot of confidence in using the product, but I did like the cloud-top cooling a little better because it seemed to do better."
I asked the forecasters if they preferred the accumulated of instantaneous fields...
"I stuck with the instantaneous for the most part, I don't think I even looked at the accumulated to be honest."
"I tended to look at the instantaneous."
Would you see a benefit in having a cloud-top cooling track?
"Yes... an overshooting top track would be very useful as well."
OTTC
Detections or magnitudes more useful?
"I looked at the detections only."
Did you see any correlations between OT detections and features developing on radar?
"Reflectivity was increasing above certain (height) levels at that time."
How often did the product correctly detect OTs that you could see on VIS/IR?
"Kinda 50/50."
"For a warning operator, I don't see this product adding much value to an on-going event..." (from survey) Why is that? Lack of detection, timeliness, applicability of product?
"Radar was more important... mix between timeliness and applicability."
"Get a good a western example case where you don't have radar."
"Maybe knock out some radars in a WES case."
PGLM
"It's an acquired taste, working with lightning data. I think it's a fundamental component in the decision making process trying to determine what's going on with the updraft... it's an interesting way of looking at it."
"With supercells I don't see any added benefit, unless it flared up right before an RFD developed... but I would have to see a lot of cases before I could determine that."
"Would be of a lot of value in low top events."
"Would be nice to see it in a non-supercell case event, like winter events."
"In terms of just lightning forecasting... I think the GLM stuff you were showing would be very useful in that area."
OVERALL / TRAINING
Overall feelings following the week...
"I'm 50/50... I'm not leaving here warm and fuzzy if that's what you're asking."
"When I came in I was very excited to have the convective initiation... I don't come out feeling as confident as I did and as excited as I did when I came in."
"The word convective initiation tool sounds awesome, maybe I went into it with high expectations as maybe seeing a tool with some probabilistic information."
How confident were you with the products following the training?
"The products were easy to understand so I was confident in using them."
What changes/additions would you like to see with the training?
Cases in the west re-iterated.
"The training itself was fine... it just seemed that it didn't perform as well as we would like to see."
I asked if the forecasters would like some sort of alert for the GOES-R products (UWCI, OTTC), so they would know when a detection was occurring, or if that would be more annoying than helpful...
"An initial alert would be nice... a continuous one would be overload."
"That would vary forecaster to forecaster."
Re-iterated the need for wind-based warning products.
"When I got really busy, I went back to the things I was used to using. I was just falling back on my normal routine."
"Would be nice on the first day to have a sort of hand-holding process to get used to the products."
"Maybe already have a base set of procedures so we don't have to spend 30 minutes setting everything up... especially on the first day."
Need cases where radar was out or nocturnal events over poor radar coverage.
UWCI
I asked about the lead times from the surveys... 15-30 mins the general consensus?
"Hard to be sure because we were arriving at the HWT after convection was developing."
"Getting in there around noon would get more accurate results."
"The case event was already initiated when I got there."
"Struggling giving up screen space during severe weather" (from survey)... is there a display you think would help?
"Having an additional head would help. We were only provided with two screens so it changed our strategy."
"Would be useful for the mesoanalyst position at the WFO."
"4-panel devoted to those products works well."
I asked the forecasters if they were ok with more signals if that meant giving up some FAR...
"I would like earlier signals, like a probability signal... which part of my CWA is going to have the best chance... Some kind of signal before there's aggitated clouds would be helpful."
I asked the forecasters whether they preferred the CI or the cloud-top cooling...
"I used them both... kind of liked them both simultaneously."
"It was hard because it seemed it was 50/50 on detecting things so I lost a lot of confidence in using the product, but I did like the cloud-top cooling a little better because it seemed to do better."
I asked the forecasters if they preferred the accumulated of instantaneous fields...
"I stuck with the instantaneous for the most part, I don't think I even looked at the accumulated to be honest."
"I tended to look at the instantaneous."
Would you see a benefit in having a cloud-top cooling track?
"Yes... an overshooting top track would be very useful as well."
OTTC
Detections or magnitudes more useful?
"I looked at the detections only."
Did you see any correlations between OT detections and features developing on radar?
"Reflectivity was increasing above certain (height) levels at that time."
How often did the product correctly detect OTs that you could see on VIS/IR?
"Kinda 50/50."
"For a warning operator, I don't see this product adding much value to an on-going event..." (from survey) Why is that? Lack of detection, timeliness, applicability of product?
"Radar was more important... mix between timeliness and applicability."
"Get a good a western example case where you don't have radar."
"Maybe knock out some radars in a WES case."
PGLM
"It's an acquired taste, working with lightning data. I think it's a fundamental component in the decision making process trying to determine what's going on with the updraft... it's an interesting way of looking at it."
"With supercells I don't see any added benefit, unless it flared up right before an RFD developed... but I would have to see a lot of cases before I could determine that."
"Would be of a lot of value in low top events."
"Would be nice to see it in a non-supercell case event, like winter events."
"In terms of just lightning forecasting... I think the GLM stuff you were showing would be very useful in that area."
OVERALL / TRAINING
Overall feelings following the week...
"I'm 50/50... I'm not leaving here warm and fuzzy if that's what you're asking."
"When I came in I was very excited to have the convective initiation... I don't come out feeling as confident as I did and as excited as I did when I came in."
"The word convective initiation tool sounds awesome, maybe I went into it with high expectations as maybe seeing a tool with some probabilistic information."
How confident were you with the products following the training?
"The products were easy to understand so I was confident in using them."
What changes/additions would you like to see with the training?
Cases in the west re-iterated.
"The training itself was fine... it just seemed that it didn't perform as well as we would like to see."
I asked if the forecasters would like some sort of alert for the GOES-R products (UWCI, OTTC), so they would know when a detection was occurring, or if that would be more annoying than helpful...
"An initial alert would be nice... a continuous one would be overload."
"That would vary forecaster to forecaster."
Re-iterated the need for wind-based warning products.
"When I got really busy, I went back to the things I was used to using. I was just falling back on my normal routine."
"Would be nice on the first day to have a sort of hand-holding process to get used to the products."
"Maybe already have a base set of procedures so we don't have to spend 30 minutes setting everything up... especially on the first day."
Need cases where radar was out or nocturnal events over poor radar coverage.
Thursday, June 17, 2010
SATCAST improvements identified
SATCAST CI nowcast overlaid on visible satellite imagery for 1945 (top left), 2002 (top right), 2015 (mid left), 2033 (mid right), and 2045 UTC (bottom center) on 17 June 2010.
Today we were able to remedy the issues we were having with the SATCAST product within our NAWIPS system. While examining today's potential severe weather outbreak over ND/MN/IA I noticed a few issues that have been relayed to the developers for future improvements. The product did not detect development over southwestern MN where some obvious convective initiation occurred between 1945 and 2045 UTC (see images above). We examined the cloud object detections provided within the output (see images below) and noticed that this area was not widely flagged as having any cloud objects within it. I discussed this with the developers and it was determined that because the clouds were developing so rapidly, the 15-minute cloud typing product used by SATCAST produced cloud types that changed so rapidly that the SATCAST algorithm's quality control threw them out. It should be noted that GOES-13 was operating in RSO during the course of the day, but due to limited computing resources it is not possible to run the product outside of the 15 minute CONUS scans at the moment. It is theorized that this issue would not exist given that the product was able to utilize RSO scans. This does help highlight a major benefit of utilizing higher temporal resolution data that will be available continuously when GOES-R is operational.
SATCAST CI nowcasts (red) and detected objects (blue) for 1945 (top left), 2002 (top right), 2015 (bottom left) and 2045 UTC (bottom right) on 17 June 2010. Note that the 2033 UTC image was not generated and the 2045 UTC image has no objects or CI nowcasts.
It also seemed as though the product was not producing output for the 2032 and 2045 UTC time periods (see images above). I also mentioned this to the developers and they discovered that the algorithm could not handle the scanning schedule changes that occurred with GOES-13 RSO. The algorithm has been changed to accommodate the scan schedule and the output has resumed.
EWP daily briefing... 6/17/2010
At the beginning of the briefing we discussed yesterday real-time IOP event over the Sterling, VA WFO CWA. We had the ability to use the PGLM output from the DCLMA for this event. Most of the warnings issued were for severe wind threats and were fairly marginal. One of the forecasters mentioned that he focused on the PGLM products because of the marginal nature of the event to try and pick out regions of greater importance since the radar and MRMS products were showing similar features for most of the convection around the area. However, due to the marginal nature of the event, no strong conclusions were drawn as to the usefulness of a lot of the experimental data. One of the forecasters brought up the idea of creating regional versions of some of the products to try and draw more information from them. This may eventually be useful for products like the CI and cloud-top cooling products since we have seen some regional dependence on the product performance (ie - diagnostic over SE US)
We also discussed the performance of the UWCI over the same area. The forecasters reiterated the lack of detection over WV/VA border from yesterday's blog post. We believe that this was due to some microphysical issues being presented in the cloud typing product that were masking out the CI signals. We mentioned that we had wished we had moved to SD sooner, which is where we ended up for the remainder of yesterday's IOP. There were a lot of signals over that area (see image above), but we were unsure as to the timing of them since we were not watching in real time. This would be a good case to look at in the future. Also, notice the lack of signals over the Sterling and State College WFO areas where we focused at the beginning of the day. Jordan Gerth discussed with the forecasters about the idea of providing a cloud-top cooling rate 'image' with no filtering, which would allow for the forecasters to see all areas of cooling/warming regardless of cloud motion or other effects that are currently removed. This would allow the forecasters decide for themselves what are false signals and may be particularly useful for determining the life cycle of MCS's and weakening supercell storms.
24-hour overshooting top (left) and thermal couplet (right) detections for 16 June 2010.
We examined the overshooting top and thermal couplet detections (see images above) and saw that both the overshooting top and thermal couplet detections did correlate well to the location of the severe weather in this case, especially over SD. However, when these were seen during the real-time IOP, it was already obvious that severe weather was occurring based on reports being received and the standard radar data. The overshooting top detections that continue further east, as well as the blob of CI nowcasts east of the tornadic storm were questioned by the forecasters since they occurred after the IOP ended and they were not sure how legitimate they were. We did look back very quickly to see what happened and it seemed as though a MCS developed later on associated with many additional warnings and it would have been nice to see the performance of the products in that instance. Again, this would be a good case to look at in the future. We will attempt to archive the data, but it may be difficult since we do not yet have dedicated disk space to do so.
The plan for today is to operate over MN and IA. This is our last chance for real-time IOPs and it looks like it should be a good one for GOES-R with the lack of cirrus in the area... assuming we get started soon enough.
Wednesday, June 16, 2010
EWP real-time IOP CI feedback
Today's IOP focused over the DCLMA domain to get some real-time PGLM experience. The forecasters broke up into two groups and localized over the Sterling, VA and State College, PA WFOs. The Sterling WFO group have been issuing severe thunderstorm warnings based on PGLM and MRMS products over the past couple hours. I was sitting with the State College WFO group as they were focusing on the UWCI products, watching for convective initiation over their area. One of the forecasters had multiple GOES-R Proving Ground products (UWCI, cloud-top cooling, overshooting top, and thermal couplet) into a 4-panel display and mentioned to me that this display strategy would be extremely useful as a situational awareness tool for monitoring satellite convective information.
GOES-13 IR imagery for 1832 (top left), 1845 (top right), 1902 (bottom left) and 1915 UTC (bottom right) on 16 June 2010. Area of interest noted by green circle.
We noticed an area of obvious convective development that was not detected by the UWCI product on the WV/VA border at 1915 UTC and the forecaster asked me to explain why no CI nowcast was made. Looking at the IR, you could see significant cooling occurring from 1832 and 1915 UTC (see above), but still no signals were seen. Jordan Gerth and I looked at the cloud typing output to see if we could draw any conclusions from that to determine what was going on (see below). Most of the area was covered by cloud types identified as 'water' or 'mixed phase'. However, there were a few spots of 'cirrus' classification over WV nearby where the CI nowcast should have been made. It seemed on visible and IR satellite that this may not have been the case, but this is hard to determine for sure. Jordan suggested that because there were these spots nearby that they may have been contaminating the spatial tests required by the algorithm to flag an area as filtered cloud-top cooling, and thus not allow for a CI nowcast to be made. This may be a fluke case where nothing can be done, but it may be useful to examine this in more detail to see if something can be improved.
UW-CIMSS Cloud typing product for 1832 (top left), 1845 (top right), 1902 (bottom left), and 1915 UTC (bottom right) on 16 June 2010. Area of interest noted by red circle.
GOES-13 IR imagery for 1832 (top left), 1845 (top right), 1902 (bottom left) and 1915 UTC (bottom right) on 16 June 2010. Area of interest noted by green circle.
We noticed an area of obvious convective development that was not detected by the UWCI product on the WV/VA border at 1915 UTC and the forecaster asked me to explain why no CI nowcast was made. Looking at the IR, you could see significant cooling occurring from 1832 and 1915 UTC (see above), but still no signals were seen. Jordan Gerth and I looked at the cloud typing output to see if we could draw any conclusions from that to determine what was going on (see below). Most of the area was covered by cloud types identified as 'water' or 'mixed phase'. However, there were a few spots of 'cirrus' classification over WV nearby where the CI nowcast should have been made. It seemed on visible and IR satellite that this may not have been the case, but this is hard to determine for sure. Jordan suggested that because there were these spots nearby that they may have been contaminating the spatial tests required by the algorithm to flag an area as filtered cloud-top cooling, and thus not allow for a CI nowcast to be made. This may be a fluke case where nothing can be done, but it may be useful to examine this in more detail to see if something can be improved.
UW-CIMSS Cloud typing product for 1832 (top left), 1845 (top right), 1902 (bottom left), and 1915 UTC (bottom right) on 16 June 2010. Area of interest noted by red circle.
Friday, June 11, 2010
EWP weekly debrief
Here is the breakdown from this week's EWP weekly debrief...
UWCI
This week was plagued by cirrus... can't remove it so we need to communicate well the limitations of the product. Forecasters were mentioning that they were constantly referring to the cloud type web page and suggested providing this into AWIPS. Will severely limit the applicability.
"If it's a good day to use it, the forecasters will use it... Most useful prior to development... right now things have to start developing before we issue products, this gives us some additional lead time."
Forecasters mentioned that the product would be useful in nighttime operations... possibly get more lead time... At night, stuff fires so quickly... perhaps providing a CI alarm in AWIPS would help situational awareness. Forecasters suggested providing a nighttime WES case for training. Lee is going to distribute web site and explain how to use it so they can look at it anytime.
Expressed interest in CI accumulated to follow CI signals through time in case they missed a scan.
Limitations in sensor scan time noted.
Forecasters mentioned the interest in providing more signals. they saw a lot of cases where CI was obvious but was not captured by the product. I asked if they were ok with the idea to sacrifice FAR for more detections...
"More times I expected to see something and didn't happened more often than not... not useful if things aren't showing where I expected to see it."
"Could you build different thresholds? Could you build one that was not so strict?"
"What about probabilistic detection? Then you can set your own threshold."
"Concerned about FAR getting too high because then it'll stop getting used."
There was a request for using additional bands... "You guys know the best bands to use... If you can get more information from other bands, go for it"
I asked if they saw the UWCI product being a precursor to lightning...
"Did not specifically check."
"I was more correlating the 35-40 dBZ"
During an event with a strong cap, the UWCI/CTC showed signals but no development occurred (or continued to occur)... perhaps provide a case of this in training.
From yesterday's IOP over Boulder, CO area... cell showed CI at 22:30 UTC... at 22:58 UTC a 30-40 dBZ occurred... showing 28 min lead time. Similar results were seen throughout the week.
A forecaster asked is testing on simulated satellite imagery planned? Yes, but currently the computation time is expensive so 5 min data would be rough.
Forecaster requested that it would be nice if the UWCI automatically loaded with satellite imagery in AWIPS.
OTTC
Forecasters mentioned they don't know what overshooting tops tell you... need more examples of this in training/literature.
Losing confidence by high threshold when you can see in visible... maybe a training issue... when you see a detection maybe it's more serious than a typical OT.
Combining with storm top divergence... "I think there's a lot of potential there."
Forecasters requested thermal couplet/overshoot detections in one product... hard to watch two different products... takes up a window in their D2D... "The more we can combine the better."
PGLM
Need to understand the importance of lightning "jumps"... show what would be significant... "What type of airmass dependence would we see with that?"
Need a rate of change product. Also, need to explain downward jumps... "What do we think is going on with the storm?"
Polarity information... needs to be mentioned that the ground based can be used in comparison.
Smoothing reducing peaks and faking a high res product.
Max-value track product would be useful... similar to rotation/hail track MRMS products.
"I think one of the problems with using lightning data in the WFO (currently) is that forecasters realize that it's (NLDN) such a small percentage of what's really going on."
"My guess is when the product becomes available it'll become a mainstream product that people are looking at all the time."
"Not necessarily going to be the main warning product, but it will be a good confirmation tool. If I had paid more attention and been more aware I could have issued my tornado warning one scan earlier." (24 May 2008 case event)
I asked if they noticed any lead time on CG from the PGLM... ~10 mins in general... canned case and real-time.
OVERALL/TRAINING
Training experience...
"Getting some simulations where the product does work out to field (WES cases) is important... hard to trust people with a Powerpoint. But be careful of putting out WES cases... 20 min articulate cases are fabulous... too long and we don't have time."
"Thankful for the canned case"
Asked forecasters how confident in the products they were after the training...
"With the UWCI I felt really good about, the other one (OTTC) was good too, I just probably don't experience it as much in operations"
"If you guys see something during real-time operations, don't hesitate to tell us something was there... don't hesitate to be the hands on instructor for the first couple days."
I asked what additional information they would like to see in the training...
"When you see a detection, provide a 'here's what it means' quicklook that we can refer to in operations."
Examples where it didn't work (cirrus, cap), and why are needed.
GOES-R products seem to be more useful before storm initiation.
Forecasters re-iterated need for object tracking and end to end multi-sensor tool... combine lightning, radar and satellite.
MRMS and GOES-R products are sparse grids... what could be done to improve your awareness that things are happening?
"Message or prompt to tell you when things are occurring."
"Some hesitation in alarms though... start to drown them out, especially when too many things trying to alert you."
"Number in lop left corner showing number of detections, like NLDN products, would be very useful."
"If there are a lot of false detections this would be hard."
Forecasters mentioned that you shouldn't be too worried about shipping the color curve information... forecasters are going to change it anyways.
"Glad you guys are here... good to have the interactions that we have and learn how these things work."
UWCI
This week was plagued by cirrus... can't remove it so we need to communicate well the limitations of the product. Forecasters were mentioning that they were constantly referring to the cloud type web page and suggested providing this into AWIPS. Will severely limit the applicability.
"If it's a good day to use it, the forecasters will use it... Most useful prior to development... right now things have to start developing before we issue products, this gives us some additional lead time."
Forecasters mentioned that the product would be useful in nighttime operations... possibly get more lead time... At night, stuff fires so quickly... perhaps providing a CI alarm in AWIPS would help situational awareness. Forecasters suggested providing a nighttime WES case for training. Lee is going to distribute web site and explain how to use it so they can look at it anytime.
Expressed interest in CI accumulated to follow CI signals through time in case they missed a scan.
Limitations in sensor scan time noted.
Forecasters mentioned the interest in providing more signals. they saw a lot of cases where CI was obvious but was not captured by the product. I asked if they were ok with the idea to sacrifice FAR for more detections...
"More times I expected to see something and didn't happened more often than not... not useful if things aren't showing where I expected to see it."
"Could you build different thresholds? Could you build one that was not so strict?"
"What about probabilistic detection? Then you can set your own threshold."
"Concerned about FAR getting too high because then it'll stop getting used."
There was a request for using additional bands... "You guys know the best bands to use... If you can get more information from other bands, go for it"
I asked if they saw the UWCI product being a precursor to lightning...
"Did not specifically check."
"I was more correlating the 35-40 dBZ"
During an event with a strong cap, the UWCI/CTC showed signals but no development occurred (or continued to occur)... perhaps provide a case of this in training.
From yesterday's IOP over Boulder, CO area... cell showed CI at 22:30 UTC... at 22:58 UTC a 30-40 dBZ occurred... showing 28 min lead time. Similar results were seen throughout the week.
A forecaster asked is testing on simulated satellite imagery planned? Yes, but currently the computation time is expensive so 5 min data would be rough.
Forecaster requested that it would be nice if the UWCI automatically loaded with satellite imagery in AWIPS.
OTTC
Forecasters mentioned they don't know what overshooting tops tell you... need more examples of this in training/literature.
Losing confidence by high threshold when you can see in visible... maybe a training issue... when you see a detection maybe it's more serious than a typical OT.
Combining with storm top divergence... "I think there's a lot of potential there."
Forecasters requested thermal couplet/overshoot detections in one product... hard to watch two different products... takes up a window in their D2D... "The more we can combine the better."
PGLM
Need to understand the importance of lightning "jumps"... show what would be significant... "What type of airmass dependence would we see with that?"
Need a rate of change product. Also, need to explain downward jumps... "What do we think is going on with the storm?"
Polarity information... needs to be mentioned that the ground based can be used in comparison.
Smoothing reducing peaks and faking a high res product.
Max-value track product would be useful... similar to rotation/hail track MRMS products.
"I think one of the problems with using lightning data in the WFO (currently) is that forecasters realize that it's (NLDN) such a small percentage of what's really going on."
"My guess is when the product becomes available it'll become a mainstream product that people are looking at all the time."
"Not necessarily going to be the main warning product, but it will be a good confirmation tool. If I had paid more attention and been more aware I could have issued my tornado warning one scan earlier." (24 May 2008 case event)
I asked if they noticed any lead time on CG from the PGLM... ~10 mins in general... canned case and real-time.
OVERALL/TRAINING
Training experience...
"Getting some simulations where the product does work out to field (WES cases) is important... hard to trust people with a Powerpoint. But be careful of putting out WES cases... 20 min articulate cases are fabulous... too long and we don't have time."
"Thankful for the canned case"
Asked forecasters how confident in the products they were after the training...
"With the UWCI I felt really good about, the other one (OTTC) was good too, I just probably don't experience it as much in operations"
"If you guys see something during real-time operations, don't hesitate to tell us something was there... don't hesitate to be the hands on instructor for the first couple days."
I asked what additional information they would like to see in the training...
"When you see a detection, provide a 'here's what it means' quicklook that we can refer to in operations."
Examples where it didn't work (cirrus, cap), and why are needed.
GOES-R products seem to be more useful before storm initiation.
Forecasters re-iterated need for object tracking and end to end multi-sensor tool... combine lightning, radar and satellite.
MRMS and GOES-R products are sparse grids... what could be done to improve your awareness that things are happening?
"Message or prompt to tell you when things are occurring."
"Some hesitation in alarms though... start to drown them out, especially when too many things trying to alert you."
"Number in lop left corner showing number of detections, like NLDN products, would be very useful."
"If there are a lot of false detections this would be hard."
Forecasters mentioned that you shouldn't be too worried about shipping the color curve information... forecasters are going to change it anyways.
"Glad you guys are here... good to have the interactions that we have and learn how these things work."
Thursday, June 10, 2010
Early UWCI detection leads to golf-ball sized hail producing storm
At 2132 UTC UWCI made a detection of a 'Pre-CI Growth' with a convective element located withing the very southern region of the Boulder, CO CWA (See figure above). At approximately 2204 UTC, radar imagery indicated the first echo > 35 dBZ with this flagged convection giving the UWCI 32 minutes of lead time on the significant radar echo. At approximately 2309 UTC the ensuing storm had spotter reports of golf ball sized hail. A success!
Additionally, as a side note, UWCI has be performing well most of the afternoon, since our four-letter friends cirrus have not been creating problems for the algorithm. A lot of the early convection that has been flagged did not amount to much, since it would die as it hit the very large cap in place, thanks to ~ 19C temperature layer at 850 mb. Radar echoes would reach 40-45 dBZ to about 4000 ft and then die. Lead times on these initial convective elements were approximately 20-30 minutes. Later indications of cloud top cooling are showing more progress with vertical development.
EWP daily briefing... 6/10/2010
SPC has issued a moderate risk over the area formerly known as "Big-12 Country" (ie - Nebraska/Colorado border). The plan will be similar to what we have done for previous IOPs with the first half of the day spent monitoring the GOES-R products for convective initiation and the second half of the day monitoring the MRMS products during warning operations.
During the briefing, Lee discussed the previous day. Unfortunately the area we targeted yesterday did not have much happen in terms of UWCI due to a widespread area of cirrus. We were able to see some overshooting top detections over northern Alabama, but they were not really associated with a lot of severe weather. There was only one thermal couplet detection but was not used by the forecasters during warning operations because they did not notice it. Most of yesterday's IOP was focused on the PGLM product, which Geoffrey Stano will post on in more detail in an upcoming post, and we got some very good feedback from that, as well as in the case example that Geoffrey has already discussed. Lee did show an area over NM/CO where the UWCI was showing 30-35 minute lead times on the first occurrence of a 35 dBZ echo on composite radar.
One important thing I noted during the discussion is that the forecasters need some sort of tool to help them forecast, and/or diagnose areas of severe winds. Right now they mentioned they have nothing that really helps them and it is really hard for them to warn for severe wind. Something to keep in mind for possible applications of GOES-R data, but I know this would be a difficult task. Nonetheless, it is an area where a obvious void in forecaster tools are present.
Wednesday, June 9, 2010
EWP daily briefing... 6/9/2010
Before the official briefing started, one of the forecasters mentioned to Lee Cronce and myself the idea of creating a filter for the CI product where cirrus is present so that the forecasters will know when the product will not be able to make any nowcasts, similar to how the radars have a certain color for areas where range folding is occurring. He mentioned that at some times they cannot understand why the product is not producing nowcasts in obvious situations of CI unless someone looks up the cloud type output for them. This was noted by Lee as a possibility for future input into the product's output.
24-hour thermal couplet detections and severe reports for 7 June 2010
During the briefing Lee presented some scan by scan output from the UWCI product over Wyoming during the 6/7 IOP. He mentioned that the first signal in the UWCI was seen at 2032 UTC, with more widespread signals occurring at 2045 UTC and beyond. The area of interest was actually located between two radars where coverage is fairly limited and the UWCI provided some information on the initiation about 15 minutes prior to detection on radar. He also showed the 24-hour thermal couplet detections and severe reports from the same event (see images above). There were a lot of detections associated with the severe reports, including one that was co-located with and prior to a report of a tornado near Scottsbluff, NE.
One of the forecasters mentioned the possibility of a GOES-R storm top divergence product. He mentioned how this would be very useful in determining storm characteristics in warning operations. I mentioned Bob Rabin's work with current GOES WV winds in producing real-time winds at various levels by tracking features in the WV imagery. From these winds he is able to calculate divergence, vorticity and wind speed contours. I showed them real-time examples from the website provided by Bob Rabin at http://cimss.ssec.wisc.edu/mesoscale_winds/. The forecasters seemed very interested in this and mentioned interest in demonstrating this in future experiments. I also made sure to point out that with GOES-R's great improvement on spatial and temporal resolution, these products will be much more accurate and will be able to capture smaller scale features. I also talked about GOES-R's increased capability for object tracking.
During the weather discussion I showed the forecasters the UW-CIMSS simulated satellite/observed satellite comparison page to see how well the NSSL-WRF was representing the day's weather. It seemed to be doing fairly well so I showed the simulated lightning threat product to see what the NSSL-WRF was showing for the possibility of lightning over the CONUS region. There seemed to be the possibility of some lightning occurring over the Nashville area later on this evening, so following the weather discussion for the day we decided to localize near Huntsville, AL for the possibility of real-time PGLM operations.
24-hour thermal couplet detections and severe reports for 7 June 2010
During the briefing Lee presented some scan by scan output from the UWCI product over Wyoming during the 6/7 IOP. He mentioned that the first signal in the UWCI was seen at 2032 UTC, with more widespread signals occurring at 2045 UTC and beyond. The area of interest was actually located between two radars where coverage is fairly limited and the UWCI provided some information on the initiation about 15 minutes prior to detection on radar. He also showed the 24-hour thermal couplet detections and severe reports from the same event (see images above). There were a lot of detections associated with the severe reports, including one that was co-located with and prior to a report of a tornado near Scottsbluff, NE.
One of the forecasters mentioned the possibility of a GOES-R storm top divergence product. He mentioned how this would be very useful in determining storm characteristics in warning operations. I mentioned Bob Rabin's work with current GOES WV winds in producing real-time winds at various levels by tracking features in the WV imagery. From these winds he is able to calculate divergence, vorticity and wind speed contours. I showed them real-time examples from the website provided by Bob Rabin at http://cimss.ssec.wisc.edu/mesoscale_winds/. The forecasters seemed very interested in this and mentioned interest in demonstrating this in future experiments. I also made sure to point out that with GOES-R's great improvement on spatial and temporal resolution, these products will be much more accurate and will be able to capture smaller scale features. I also talked about GOES-R's increased capability for object tracking.
During the weather discussion I showed the forecasters the UW-CIMSS simulated satellite/observed satellite comparison page to see how well the NSSL-WRF was representing the day's weather. It seemed to be doing fairly well so I showed the simulated lightning threat product to see what the NSSL-WRF was showing for the possibility of lightning over the CONUS region. There seemed to be the possibility of some lightning occurring over the Nashville area later on this evening, so following the weather discussion for the day we decided to localize near Huntsville, AL for the possibility of real-time PGLM operations.
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