Today marks the end of 4 weeks of operations in the EWP. Today we had the opportunity to debrief the forecasters on their experience here over the past week.
SATCAST / UW Cloud-top Cooling
- Yesterday's event over Boulder CWA... "We did try to warn on the CTC a couple times with ongoing severe to the north, the first storm quickly disappeared, but the second one was successful... we did get 1.5" hail out of it."
- "I can definitely see the utility of the products in focusing your attention on what is developing."
- "There were a couple instances where the SATCAST would have a lot of 'confetti', but there weren't any really strong signals... it really showed the utility of having the strength of signal instead of a yes/no."
- "The probabilities for the SATCAST did seem to match up with the overall occurrence of CI."
- "I may have only seen one case this whole week where the -20 C /15 mins signal in the CTC had any severe after it... I think there could be more work done to fine tune those values." - There seems to be some environmental dependance that could be playing a role in how successful the threshold values are in relating to severe weather... It has performed well over past weeks, but in some situations (like the past couple days) the occurrence of severe after a strong cooling rate may be less common.
- "I really liked that 'Ultimate-CI' 4-panel you guys had... that was nice... I would steal that."
Simulated Satellite
- "I found that the placement of convection was really good... the biggest weakness was the timing and the coverage of the storms... I see this as a 'top of the pyramid' product where I will start to get an idea of what's going on over my CWA."
- "It also picked up on the non-convective stuff (jet streaks/shortwaves) really well with the WV."
- "It would be great to get this in GFE."
- "I looked at the band difference, but I didn't really see the utility of it... granted I was more focused on the IR and WV which was more intuitive to me."
- "When we got set up, there was almost always stuff on radar, so we didn't really have much of a use for it."
Nearcast
- "I used it both as a forecast tool and an analysis tool."
- "A lot of the time this week the clouds were just too thick and made it hard to use."
- "I put the OUN WRF reflectivity on one panel with the CAPE and Theta-e products... the convection followed the CAPE/theta-e areas well... it was an interesting way to display it."
- "It was nice that you could use the GOES-E and GOES-W and overlap them to give you the complete picture... the values were a little different where they overlapped, but it still gave you a good picture."
- "It would probably be more useful in the early afternoon."
Sounder Airmass RGB
- "We ingest the other NASA sport RGB products and the color tables were so different for the airmass product that I got a little confused." - They were referring to the MODIS version of the RGB airmass, which does have some different color aspects.
- "I did look at it once and it did pick up on a lot of the larger scale features very well."
PGLM
- Yesterday's event over Sterling CWA... Had a lot of trouble with sensors failing over DCLMA and causing serious detection efficiency issues.
- "Like I said the other day... 5- and 15-minute composites would be great in addition to the 1-minute data."
- "The color curve was a little hard to see, especially for the lower flash amounts."
- "Lightning jumps aren't easily seen in the 2D gridded display... especially at 8km."
- "It would be really cool to see this over smoke plumes... we have seen some CG strikes from smoke plumes before."
Overall / Training
- It was reiterated that for some of these limited coverage datasets (ie - PGLM), it would be nice to have a map of the coverage.
- "The biggest negative was the satellite outage issue... it always seemed to happen right when everything happened." - 1800 and 2100 UTC are prime times for convection... and are also when 30-minute full disk scans occur.
- "Winds an turbulence are our biggest threats (CWSU aviation)... especially relating to non-convective weather and they are hard to pick up on with radar data alone."
- "I thought the change to having a training shift before you arrive was a great idea... it was overall very smooth."
- "I definitely felt more comfortable finding the products yesterday than I did day 1... It might be helpful to just sit down for an hour or two with someone and load the products."
- "Having procedures for the products really helped."
- "Having everything in AWIPS II was fantastic... we really got some good hands on experience with how the products will be used in the future."
- "I really liked the discussions with the developers... it really helped us understand how the products worked."
- "Having a level of uncertainty or confidence displayed within the products is very useful."
Friday, June 8, 2012
Thursday, June 7, 2012
BOU: Here we go!
Forecaster comments from EWP blog...
Well…we decided to issue our first experimental warning based on the UW-CTC. Let’s see what kind of lead time we get!
CTC rates were around -20C/15 min and we are just beginning to see some reflectivity.
We will update to let you know if we get any verification or if this turns out to be a false alarm!
Update: A great question was just posed: do you plot the warning downstream of the developing storm based on the Warn-on-Forecast? Or do you just use the CTC as a ‘red flag’ and follow the development as it progresses…issuing the warning at a later time?
CTC (upper right image on left panel) with first severe thunderstorm warning (right panels)
Well…we decided to issue our first experimental warning based on the UW-CTC. Let’s see what kind of lead time we get!
CTC rates were around -20C/15 min and we are just beginning to see some reflectivity.
We will update to let you know if we get any verification or if this turns out to be a false alarm!
Update: A great question was just posed: do you plot the warning downstream of the developing storm based on the Warn-on-Forecast? Or do you just use the CTC as a ‘red flag’ and follow the development as it progresses…issuing the warning at a later time?
CTC (upper right image on left panel) with first severe thunderstorm warning (right panels)
Update: 2207z….
We issued another warning based on CTC! We seemed to kill any
potential with the first CTC-based warning… perhaps this one will work
out!
Trends on MESH and reflectivity have improved on this storm and now appears severe on radar.
Update: 5:43pm CDT... VERIFIED! 1.50″ 4:30pm local time (MDT)!! The initial warning was issued at 4:07pm MDT.
CI products on the front range
Forecaster comments from EWP blog..
Watching for CI in CO. We have noted moderate to high SOS hits on the
higher terrain of CO west of DEN (1930Z and 2015Z images shown). Up to
this point this activity has yet to convect. Conditions are ripe so we
will see when it does take off.
Update: This initial activity did not convect.
1932 UTC
2015 UTC
Update: This initial activity did not convect.
BOU: Playing with 4 Panel Displays
Forecaster comments from EWP blog...
Initially, I had the current radar in the upper left panel and the GOES East and GOES West CAPE, Theta-E diff and PW diff combined into a 4-Panel. Out of curiosity, I decided to load the OUNWRF 1km AGL Derived Radar Reflectivity into the upper right panel. It was kind of interesting to see how the derived reflectivity moved into the more favorable areas of CAPE, Theta-e diff low-mid lvls, and PW diff.
The GOES East / GOES West products are a bit rough to read, but its a nice ‘generalization’.
Initially, I had the current radar in the upper left panel and the GOES East and GOES West CAPE, Theta-E diff and PW diff combined into a 4-Panel. Out of curiosity, I decided to load the OUNWRF 1km AGL Derived Radar Reflectivity into the upper right panel. It was kind of interesting to see how the derived reflectivity moved into the more favorable areas of CAPE, Theta-e diff low-mid lvls, and PW diff.
VISIT Blog: "1-Minute GOES Imagery over Colorado Severe Storms"
Great blog post from Dan Lindsey at CIRA regarding the 1-minute Super-Rapid Scan Operations called for GOES-15 (GOES-West) yesterday. Example of how higher temporal resolution imagery (like that which will be available from GOES-R's Advanced Baseline Imager) can be used by forecasters.
http://rammb.cira.colostate.edu/training/visit/blog/index.php/2012/06/07/1-minute-goes-imagery-over-colorado-severe-storms/
http://rammb.cira.colostate.edu/training/visit/blog/index.php/2012/06/07/1-minute-goes-imagery-over-colorado-severe-storms/
BOU view of the Nearcast
Forecaster comments from EWP blog...
View of the GOES-R Nearcast values of of CAPE and thetae difference. In
this particular case BOU was located on the GOES E and W boundaries and
had two values shown for each parameter. In this example, the E
satellite showed more unstable values for the same point (in comparison
to the west). As pointed out, this could be correct since each satellite
may be looking at different effective levels. Regardless, these
products showed the best axis of instability along the eastern 1/3 of CO
(along the front range), with the greatest instability maintaining
itself across NE CO well past 00Z.
LWX: Watching for lightning…and seeing confetti
Forecaster comments from EWP blog...
We’ve started out watching the LWX CWA in the hopes of getting a feel for the DC Lightning Mapping Array. The equipment, as well as the storms, are not cooperating however. So, we have been monitoring the CI products in the hopes of seeing some more significant storms pop up. The UAH CI algorithm has been treating us to a “confetti” pattern such as in the upper left on the IR image, and the lower right on the visible. This kind of appearance is not surprising given the relative cool pool of air in place across the northeast U.S. We have gotten a couple of minor UW CI CTC hits that developed into a couple of decent showers on the LWX 88D, which can be seen in the upper right panel. So far though, not a lot of lightning data to look at, and our domain may be shifting soon.
We’ve started out watching the LWX CWA in the hopes of getting a feel for the DC Lightning Mapping Array. The equipment, as well as the storms, are not cooperating however. So, we have been monitoring the CI products in the hopes of seeing some more significant storms pop up. The UAH CI algorithm has been treating us to a “confetti” pattern such as in the upper left on the IR image, and the lower right on the visible. This kind of appearance is not surprising given the relative cool pool of air in place across the northeast U.S. We have gotten a couple of minor UW CI CTC hits that developed into a couple of decent showers on the LWX 88D, which can be seen in the upper right panel. So far though, not a lot of lightning data to look at, and our domain may be shifting soon.
BOU: Another busy day for Traffic Management folks!
Forecaster comments from EWP blog...
Another day…same problem…convection firing up in the vicinity of some major jet routes and arrival gates in the DEN airspace. That means traffic headaches not only for controllers in Denver air space…but for people in ZKC, ZFW, ZAB…etc. You get the idea.
Once again, I’m able to test out the Sim Sat products. Already some activity firing up along the front range….but had I come in at 0530 (for a normal shift), I could have used the Sim Sat products to provide TMU with some good information for their planning purposes. Figure 1, below, illustrates the 19z Sim Sat compared to the 19z IR (lower left). You can see that the Sim Sat products have under-forecast the convection – one of the major limitations of the tool. However – the general location and trends are highlighted very well. With the exception of the development over BOU.
Another day…same problem…convection firing up in the vicinity of some major jet routes and arrival gates in the DEN airspace. That means traffic headaches not only for controllers in Denver air space…but for people in ZKC, ZFW, ZAB…etc. You get the idea.
Once again, I’m able to test out the Sim Sat products. Already some activity firing up along the front range….but had I come in at 0530 (for a normal shift), I could have used the Sim Sat products to provide TMU with some good information for their planning purposes. Figure 1, below, illustrates the 19z Sim Sat compared to the 19z IR (lower left). You can see that the Sim Sat products have under-forecast the convection – one of the major limitations of the tool. However – the general location and trends are highlighted very well. With the exception of the development over BOU.
CYS: Getting started
Forecaster comments from EWP blog...
We have big storms as we sit. Limited 3D-VAR domain and data today. -20C is about 17.5kt as we sat down and have 55dBZ over 25kft out the door.
Cooling was earlier with our storms with about 10-15 minutes heads up for 1 or 2 of them.
We have big storms as we sit. Limited 3D-VAR domain and data today. -20C is about 17.5kt as we sat down and have 55dBZ over 25kft out the door.
Cooling was earlier with our storms with about 10-15 minutes heads up for 1 or 2 of them.
EWP daily debrief 6/7
Below are some of the feedback we collected during today's debrief of the EWP forecasters...
SATCAST / UW Cloud-top Cooling
- "We had quite an issue with missing data... it wouldn't update for 30 minutes and by that point we were already behind with things." - This is due to the 3 hourly 30-minute full disk scans that currently plague GOES data.
- "We had a -33 C / 15 mins signal in the CTC and nothing happened." - See this blog post
- "Once we tried to zoom in on a local scale and it (SATCAST) looked a little offset from the visible data."
- "Once you're in warning mode they're not of much value... you should really try to look at these things more prior to warning operations... you would need more resources (personnel) to look at these products when you're trying to issue warnings."
- "They worked fine for me until we started getting anvil cirrus overhead."
Nearcast
- The CAPE product lined up well with some of the analysis data and where the more significant storms ended up forming.
Simulated Satellite
- "It did a really good job yesterday, especially because it was run the day before... it would be nice if we had a 12 UTC run as well."
- There is interest in running this on more models.
- Sky grids in GFE would be incredibly useful.
- "They look seductive because they resemble the actual data so well."
PGLM
- "There was a 20 minute lead time between the first IC and the first CG."
- "It would be nice to see a 5- or 15-minute accumulation of the lightning data as well... when we used the 1-minute data it was hard to go back in time very far because you needed a lot of frames and that got fairly frustrating."
Overall / Training
- "I'm concerned that the bandwidth issue is going to be difficult to deal with... I want to get some of these satellite products back to the office to show people, but I have a hard enough time just loading a satellite image loop."
SATCAST / UW Cloud-top Cooling
- "We had quite an issue with missing data... it wouldn't update for 30 minutes and by that point we were already behind with things." - This is due to the 3 hourly 30-minute full disk scans that currently plague GOES data.
- "We had a -33 C / 15 mins signal in the CTC and nothing happened." - See this blog post
- "Once we tried to zoom in on a local scale and it (SATCAST) looked a little offset from the visible data."
- "Once you're in warning mode they're not of much value... you should really try to look at these things more prior to warning operations... you would need more resources (personnel) to look at these products when you're trying to issue warnings."
- "They worked fine for me until we started getting anvil cirrus overhead."
Nearcast
- The CAPE product lined up well with some of the analysis data and where the more significant storms ended up forming.
Simulated Satellite
- "It did a really good job yesterday, especially because it was run the day before... it would be nice if we had a 12 UTC run as well."
- There is interest in running this on more models.
- Sky grids in GFE would be incredibly useful.
- "They look seductive because they resemble the actual data so well."
PGLM
- "There was a 20 minute lead time between the first IC and the first CG."
- "It would be nice to see a 5- or 15-minute accumulation of the lightning data as well... when we used the 1-minute data it was hard to go back in time very far because you needed a lot of frames and that got fairly frustrating."
Overall / Training
- "I'm concerned that the bandwidth issue is going to be difficult to deal with... I want to get some of these satellite products back to the office to show people, but I have a hard enough time just loading a satellite image loop."
Wednesday, June 6, 2012
CYS: Loved the Sim Sat Products!
Forecaster comments from EWP blog...
I am very pleased with how well the Sim Sat products performed today. This event was the first time I was able to fully utilize these tools! Based on the training…the sim sat products tended to under-do the convection…here, you can see that the sim sat OVER did some of the convection…most notably over BOU.
Had I used this application in my forecast, TMU would have been very happy with me! This would have been fantastic for planning/re-routing purposes.
I am very pleased with how well the Sim Sat products performed today. This event was the first time I was able to fully utilize these tools! Based on the training…the sim sat products tended to under-do the convection…here, you can see that the sim sat OVER did some of the convection…most notably over BOU.
Figure 1: Sim Sat Forecast vs Real Time
Had I used this application in my forecast, TMU would have been very happy with me! This would have been fantastic for planning/re-routing purposes.
CYS: Awesome CI rate…going for lead time!
Forecaster comments from EWP blog...
Was starting to think that anvil contamination would limit use of the CI products by this point. However, the algorithm put out a nice little surprise. The cooling rate tops out at -33C/15 min…which is likely the highest anyone has seen so far! Went ahead and quickly issued a warning on it…going for good lead time…and took a chance and called for 2 inch diameter hail. Let’s see what happens!
Was starting to think that anvil contamination would limit use of the CI products by this point. However, the algorithm put out a nice little surprise. The cooling rate tops out at -33C/15 min…which is likely the highest anyone has seen so far! Went ahead and quickly issued a warning on it…going for good lead time…and took a chance and called for 2 inch diameter hail. Let’s see what happens!
CYS: Severe storms now popping…and the SimSat products pretty much nailed it
Forecaster comments from EWP blog...
Starting to issue some warnings now in the CYS CWA for some brewing supercells. Took a moment to reevaluate the simulated satellite products. Note in particular the top two panels…the simsat is on the left, the actual GOES IR image is on the right. The model did an excellent job in generating convection in southeast Wyoming. The timing was maybe a touch off, but this is certainly acceptable for such a highly detailed guidance product which ran the previous night!
Starting to issue some warnings now in the CYS CWA for some brewing supercells. Took a moment to reevaluate the simulated satellite products. Note in particular the top two panels…the simsat is on the left, the actual GOES IR image is on the right. The model did an excellent job in generating convection in southeast Wyoming. The timing was maybe a touch off, but this is certainly acceptable for such a highly detailed guidance product which ran the previous night!
CYS: The cap is eroding…but storms are still sub-severe. Looking at CI products
Forecaster comments from EWP blog...
Working the Cheyenne CWA, we have been waiting for the cap to erode, and it has started to during the past hour. So far, though, the storms have been tame. Monitoring the CI products reinforces that thought. The upper right panel in the image below shows the instantaneous cooling rate at cloud top. Most of these have been at the rate of -10C per 15 minutes. This is roughly half of the typical rate that one might see as a precursor to severe storms. While the convection is weak so far, we have potential for more interesting rotating storms later.
Working the Cheyenne CWA, we have been waiting for the cap to erode, and it has started to during the past hour. So far, though, the storms have been tame. Monitoring the CI products reinforces that thought. The upper right panel in the image below shows the instantaneous cooling rate at cloud top. Most of these have been at the rate of -10C per 15 minutes. This is roughly half of the typical rate that one might see as a precursor to severe storms. While the convection is weak so far, we have potential for more interesting rotating storms later.
CI products: UAH strength of signal scheme in upper left, instantaneous
cloud top cooling rate in upper right, accumulated cooling rate in
lower left, ice cloud mask in lower right.
Nearcast CAPE over CO
GOES-15 Super-Rapid Scan over NE Colorado
GOES-15 SRSO was called to support the DC3 campaign over NE Colorado today. CIRA has provided us with a web link that we are sharing with the forecasters in the HWT. The link to the imagery can be found here...
http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=dev/lindsey/loops/goes15&image_width=1020&image_height=720
http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=dev/lindsey/loops/goes15&image_width=1020&image_height=720
CYS: Convective Initiation and Impacts to Aviation
Forecaster comments from EWP blog...
Today is a great opportunity to test the Simulated Satellite products! I created a 4 panel to compare the sim sat products with the real time IR. I also overlaid jet routes to get a better picture of the potential impacts to aviation. One downfall to using the jet route overlay in AWIPS is that unless you’re familiar with the routes, you have no idea what you’re looking at. Maybe some day we can get a mouse-over feature with the jet routes so that the user can identify the names of the jet routes.
Figure 1 is the 4 panel comparison of the simulated products and real time IR. Figure 2 is the simulated IR and water vapor with jet routes overlaid. You can see that at 22Z, should the forecast be right, that re-routs will definitely be in order! I am eager to see how accurate this product is today…this could mean great things for the CWSU/FAA folks! Figure 3 is just a zoomed in 22z Sim Sat WV forecast.
The image in the lower right is the 10.4-12.3um IR which can help to show areas of low level moisture (yellow). As the column continues to moisten, you’ll see the areas of blue develop. Blue areas indicate a difference of zero.
Stay tuned to see how well the Simulated Satellite products work out!
Today is a great opportunity to test the Simulated Satellite products! I created a 4 panel to compare the sim sat products with the real time IR. I also overlaid jet routes to get a better picture of the potential impacts to aviation. One downfall to using the jet route overlay in AWIPS is that unless you’re familiar with the routes, you have no idea what you’re looking at. Maybe some day we can get a mouse-over feature with the jet routes so that the user can identify the names of the jet routes.
Figure 1: SimSat Compare with Real Time IR (lower left)
Figure 1 is the 4 panel comparison of the simulated products and real time IR. Figure 2 is the simulated IR and water vapor with jet routes overlaid. You can see that at 22Z, should the forecast be right, that re-routs will definitely be in order! I am eager to see how accurate this product is today…this could mean great things for the CWSU/FAA folks! Figure 3 is just a zoomed in 22z Sim Sat WV forecast.
Figure 2: 22z SimSat Forecast
The image in the lower right is the 10.4-12.3um IR which can help to show areas of low level moisture (yellow). As the column continues to moisten, you’ll see the areas of blue develop. Blue areas indicate a difference of zero.
Figure 3: Convective Initiation Forecast and BOU Impacts
Stay tuned to see how well the Simulated Satellite products work out!
DFW: 06 JUNE
Forecaster comments from EWP blog...
Cloud top cooling at 1745 showed evolution but it was already in place and immediately on radar. Lightning flash density peaking over 50 flashes minute near Red River. MESH got hail over 1 inch near Red River and we found we had KDYX which showed good rotation for storm along line.
Cloud top cooling at 1745 showed evolution but it was already in place and immediately on radar. Lightning flash density peaking over 50 flashes minute near Red River. MESH got hail over 1 inch near Red River and we found we had KDYX which showed good rotation for storm along line.
BOU: OUN-WRF / Synthetic Satellite on Storm Initiation
Forecaster comments from EWP blog...
The above two images predict storm initiation at 19z. The top image is a
4-panel of WRF-derived synthetic satellite products and the bottom
image is a single panel OUNwrf 1km agl reflectivity from roughly the
same time. Both products show rapid thunderstorm initiation around
19-1930z. Given recent vis satellite imagery, this appears too early.
Only time will tell…
EWP daily debrief 6/6
Yesterday was a rough day for the satellite products due to extensive cloud cover, but we were able to get some feedback from today's debrief with the EWP forecasters...
SATCAST / UW Cloud-top Cooling
- "There was a lot of cloud cover over the area, so there wasn't a lot of opportunity to use it (CTC)... but we did have one case over the ocean that worked very well and I would have issued a special marine warning for it."
Nearcast
- Forecasters did not find much utility in it yesterday due to ongoing cloud cover issues, especially over FL/GA.
PGLM
- Forecasters mentioned that they would like to have a value of total flashes in the upper corner of the AWIPS II display much like NLDN does... and if possible, a ratio of IC-CG as well.
SATCAST / UW Cloud-top Cooling
- "There was a lot of cloud cover over the area, so there wasn't a lot of opportunity to use it (CTC)... but we did have one case over the ocean that worked very well and I would have issued a special marine warning for it."
Nearcast
- Forecasters did not find much utility in it yesterday due to ongoing cloud cover issues, especially over FL/GA.
PGLM
- Forecasters mentioned that they would like to have a value of total flashes in the upper corner of the AWIPS II display much like NLDN does... and if possible, a ratio of IC-CG as well.
Tuesday, June 5, 2012
OUN (LBB): CI with Boundary Interaction?
Forecaster comments from EWP blog...
Agitated cumulus on visible satellite noted over Childress County. UAH CI values currently at 53, but have been steadily increasing the last few volume scans. Outflow boundary from western Oklahoma storms continues to push southwestward. Watching to see if storms will develop if the boundary helps initiate convection. 21Z OUN WRF now showing a second line of convection developing along the southwest boundary. Stay tuned.
Agitated cumulus on visible satellite noted over Childress County. UAH CI values currently at 53, but have been steadily increasing the last few volume scans. Outflow boundary from western Oklahoma storms continues to push southwestward. Watching to see if storms will develop if the boundary helps initiate convection. 21Z OUN WRF now showing a second line of convection developing along the southwest boundary. Stay tuned.
OUN: An Aviation Perspective…
Forecaster comments from the EWP blog...
The image below (Figure 1) illustrates the potential for convective initiation, using the UAH-CI tool. The high altitude jet routes overlaid with the CI and latest satellite data show the potential impacts to aviation. I expect that the CI tool will be very useful in operations – especially at the CWSUs.
Figure 1: Convective Initiation Impacts on Aviation
TMU is always asking about timing and location of convective development. Things become problematic when routes need to be changed at the last second as a result of developing thunderstorms. If we have more tools to provide a larger lead time, TMU personnel can plan farther in advance – which leads to saving money and time…and stress!
The image below (Figure 1) illustrates the potential for convective initiation, using the UAH-CI tool. The high altitude jet routes overlaid with the CI and latest satellite data show the potential impacts to aviation. I expect that the CI tool will be very useful in operations – especially at the CWSUs.
Figure 1: Convective Initiation Impacts on AviationTMU is always asking about timing and location of convective development. Things become problematic when routes need to be changed at the last second as a result of developing thunderstorms. If we have more tools to provide a larger lead time, TMU personnel can plan farther in advance – which leads to saving money and time…and stress!
OUN: Don’t put all your chips into one [or two] products…
Forecaster comments from EWP blog...
One thing I’ve begun to wonder is will there be a loss of SA when a forecaster sees an area of “potential development”. The image below (Figure 1) illustrates the UAH-CI in the upper-left panel, while the upper-right panel shows the UW-CTC. My concern is that someone might see a CI area in the 60-70% confidence range and lose their sense of SA as they wait for further development…and the CTC algorithm to hopefully pick up on the developing storm.The UW-CTC product is designed to only pick up on the stronger development…which could easily lead to missing weaker convection. Not only that, but if any bit of the anvil goes near another developing cell…the algorithms will not pick up the newly developing thunderstorms…could end up to missing a warning.
One thing I’ve begun to wonder is will there be a loss of SA when a forecaster sees an area of “potential development”. The image below (Figure 1) illustrates the UAH-CI in the upper-left panel, while the upper-right panel shows the UW-CTC. My concern is that someone might see a CI area in the 60-70% confidence range and lose their sense of SA as they wait for further development…and the CTC algorithm to hopefully pick up on the developing storm.The UW-CTC product is designed to only pick up on the stronger development…which could easily lead to missing weaker convection. Not only that, but if any bit of the anvil goes near another developing cell…the algorithms will not pick up the newly developing thunderstorms…could end up to missing a warning.
OUN: CI products
Forecaster comments from EWP blog...
UAH Convective Initiation images showed a brief value of 65 in northeast Comanche County but the UW_CTC product never showed a cloud top cooling value. This seems to be due to the proximity of the cluster of cells to the west. The cell in northeast Comanche County was very slow to develop, but did become very strong and actually produced a 62 mph wind gust. Additionally, the MESH showed hail sizes of over one inch.
UAH Convective Initiation images showed a brief value of 65 in northeast Comanche County but the UW_CTC product never showed a cloud top cooling value. This seems to be due to the proximity of the cluster of cells to the west. The cell in northeast Comanche County was very slow to develop, but did become very strong and actually produced a 62 mph wind gust. Additionally, the MESH showed hail sizes of over one inch.
UAH signal at 1915z in NE Comanche Co.
Cell first noted at 1925z
One inch hail detected 45 minutes after initial reflectivity blob on radar, and 55 minutes after UAH signal.
Evaluation of UAHCI early on in MLB
Forecaster comments from EWP blog...
Looking across FL, much of the area was obscured by thick high clouds,
making the CI products impossible to calculate/use. However, at 1710Z,
the UAHCI algorithm did indicate possible CI just off the eastern FL
coast, with a relatively low strength of signal of 30-40. Of note, the
UWCTC algorithm did not hit on this cloud mass at all. As the follow
image at 17:45Z shows, the band of clouds with a low SOS did not develop
and actually diminished. This is within the expected outcome given the
low SOS.
MLB: Checking out the RGB Airmass GOES Sounder product
Forecaster comments from EWP blog...
Thunderstorms over our region are fairly tame at the moment, so I began checking out some other interesting products. Here is a shot of the RGB Airmass product produced by the GOES sounder. GOES-R will have a similar image. This basically takes information from four different wavelengths and combines them into one image. Reddish colors here are high PV air associated with the jet…notice the band across the western Great Lakes. Blue indicates a cooler airmass with associated midlevel clouds…notable across the northeast US. Greenish colors are thicker low-level clouds with a more moist airmass…not surprisingly, the southeast US shows this. Yellowish colors, such as over the Pacific Northwest, are low-level clouds in a cooler airmass. White areas are deep cloud decks, often over convection, like Florida and the eastern Gulf. Looping this product can show airmass movement and jet position/structure. This can be useful as a check against NWP models. I’ve posted both the RGB product (top) and the normal IR image at the same time (bottom) for comparison.
Thunderstorms over our region are fairly tame at the moment, so I began checking out some other interesting products. Here is a shot of the RGB Airmass product produced by the GOES sounder. GOES-R will have a similar image. This basically takes information from four different wavelengths and combines them into one image. Reddish colors here are high PV air associated with the jet…notice the band across the western Great Lakes. Blue indicates a cooler airmass with associated midlevel clouds…notable across the northeast US. Greenish colors are thicker low-level clouds with a more moist airmass…not surprisingly, the southeast US shows this. Yellowish colors, such as over the Pacific Northwest, are low-level clouds in a cooler airmass. White areas are deep cloud decks, often over convection, like Florida and the eastern Gulf. Looping this product can show airmass movement and jet position/structure. This can be useful as a check against NWP models. I’ve posted both the RGB product (top) and the normal IR image at the same time (bottom) for comparison.
JAX:Cloud top cooling and marine supercells
Forecaster comments from EWP blog...
CTC and CI products have shown promise today despite shield of
cirrus/anvil blowoff. The above image illustrates large CTC at 1910z.
Within 15 minutes of this image, a line of small discrete supercells
developed just offshore.
PGLM in AWIPS II
EWP daily debrief 6/5
Yesterday's event was mainly spent familiarizing the forecasters with AWIPS II, how to load the products and setting up procedures, so active operations were somewhat limited. Below are some of the feedback we gathered during today's debrief.
SATCAST / UW Cloud-top Cooling
- "We looked at it (CI and CTC) after the fact and it looked liked it picked up on the initiation really well."
- "There were only two cells that had advanced warning on the CTC, but the rest fell apart right after the signal."
- "Given yesterday's setup, it was very marginal, pulse-type storms... I was pretty impressed by the way the CI product handled it with cells going up all over... the CTC product really helped key in on what cell was most significant."
PGLM
- For some reason the West TX LMA data was not meshing well with the way the domain was set up in AWIPS II, so flash amounts were low and offset... we had to use an external WDSSII display for the Lubbock forecasters to look at.
- "For the limited amount we got to look at, I liked the PGLM a lot... it was very very handy."
Nearcast
- Cloud cover mostly obscured the areas of interest yesterday (Lubbock/Amarillo) due to ongoing convection.
- Forecasters really liked the CAPE product and look forward to seeing it throughout the week.
- "There were a few holes around where observations were made and it matched up with some of the meso data."
Overall / Training
- "It would be helpful to show the boundaries for the products that don't cover the entire area."
SATCAST / UW Cloud-top Cooling
- "We looked at it (CI and CTC) after the fact and it looked liked it picked up on the initiation really well."
- "There were only two cells that had advanced warning on the CTC, but the rest fell apart right after the signal."
- "Given yesterday's setup, it was very marginal, pulse-type storms... I was pretty impressed by the way the CI product handled it with cells going up all over... the CTC product really helped key in on what cell was most significant."
PGLM
- For some reason the West TX LMA data was not meshing well with the way the domain was set up in AWIPS II, so flash amounts were low and offset... we had to use an external WDSSII display for the Lubbock forecasters to look at.
- "For the limited amount we got to look at, I liked the PGLM a lot... it was very very handy."
Nearcast
- Cloud cover mostly obscured the areas of interest yesterday (Lubbock/Amarillo) due to ongoing convection.
- Forecasters really liked the CAPE product and look forward to seeing it throughout the week.
- "There were a few holes around where observations were made and it matched up with some of the meso data."
Overall / Training
- "It would be helpful to show the boundaries for the products that don't cover the entire area."
Monday, June 4, 2012
LUB: Day 1 – Getting Familiar with Products
Forecaster comments from EWP blog...
Shortly after entering the lab, thunderstorms quickly fired up over our area of responsibility. While getting familiar with the new forecasting and diagnostic tools, we were quickly thrown into a “warning operations” situation.
The OUNWRF did a fairly good job handling the timing and location of
convective initiation this afternoon (Figure 1). Along with using the
OUNWRF, we also tested the UW-CIMSS Cloud Top Cooling tool. The UW-CTC
tool did a great job picking up the areas of developing convection
across the CWA This afternoon. UW-CTC algorithm seemed to have only
two”false alarms”, one of which being the result of some high clouds. It
was pretty easy to identify the “false alarm” as the CTC rates were
extremely low (on the order of -5C/15min), compared to CTC rates around
-20C/15min (observed with most of the developing activity).
The second “false alarm” occurred when the CTC algorithm tagged a
developing storm with CTC rates from -15 to -20C/15min (figure 3). After
warning on this storm, we waited for LSRs and never saw a report to
verify the warning.
Despite a couple of false alarms, we were very pleased with the
performance of the OUNWRF with respect to the storms becoming outflow
dominate and producing more wind damage than hail. We received wind gust
reports greater than 60mph in the LBB area, as well as numerous downed
trees. Figure 4 below illustrates the surface max hourly wind speed.
Typically winds greater than 20m/s should raise heightened awareness and
the potential for damaging winds.
Had we a little more time to become familiar with the products and get
“spun up” with our procedures and whatnot…the Convective Initiation tool
would have helped us greatly. Figure 5 below shows the CI application
combined with vis sat imagery. The algorithm picks up the CI very
nicely…this storm eventually blew up and was one of the larger storms of
the day. The storm produced very large hail.The UAH-CI application
continued to be quite helpful to us during the rest of the shift.
Shortly after entering the lab, thunderstorms quickly fired up over our area of responsibility. While getting familiar with the new forecasting and diagnostic tools, we were quickly thrown into a “warning operations” situation.
AMA: Warn on CI “miss?”
Forecaster comments from EWP blog...
We have issued a couple warnings on marginal storms that did not give strong CI signals. On this image, I warned on the middle cell in Hansford County (reflectivity on bottom left). Note the lack of instantaneous or accumulated cloud top cooling for this area. We are looking for downburst winds and maybe some subsevere hail from this storm. The CI algorithms have been doing well in other CWAs like Lubbock, but may have missed one here, pending verification.
We have issued a couple warnings on marginal storms that did not give strong CI signals. On this image, I warned on the middle cell in Hansford County (reflectivity on bottom left). Note the lack of instantaneous or accumulated cloud top cooling for this area. We are looking for downburst winds and maybe some subsevere hail from this storm. The CI algorithms have been doing well in other CWAs like Lubbock, but may have missed one here, pending verification.
AMA: First potential UW/CI cell
Forecaster comments from EWP blog...
Here is the first cell that is close to -20C/15 min in the AMA area
today. Expecting storms to be mainly of the up and down variety due to
lack of flow/shear. Will be watching this one to see what happens.
AMA: Convective initiation in a non-supercell environment
Forecaster comments from EWP blog...
Kicking off the 4th week in the HWT at CWA AMA. Will be interesting to
see how the convective initiation products handle more or less “popcorn”
type convection beneath very weak upper flow and mid-level ridging.
Image above shows several areas of moderate to high-indication CI in the
next hour.
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