End of Week 2

Overall weekly thoughts and suggestions for future training:

• Morning discussions and surveys were good
• Liked having the experts here
• Four day length of testing was good, 12-8 PM shifts work well
• Comfortable environment
• Appreciate getting reports and live picturesSuggestion to label the work stations, so everyone knows which CWA are being operated by whom
• Public should see more of what’s being done here, what they are funding and that it’s important…cool stuff
• Video surveys would be good, easy to sit in front of a webcam at the end of the day
• Change the surveys each day, make them more relevant to the day’s events

EWP Week 2 End of Day 4...Thoughts and Feedback

Our forecasters ended the day in the Omaha, NE and Sioux Falls, SD offices.  Storms developed during the afternoon hours over far northeastern NE, southeastern SD and western IA.

• ·       GOES-16 ABI Imagery and products (Imagery/Derived/Channel Differences/RGB Composites)

o   Played with Channel 1-15…was able to see the difference in temperatures for 13,14,15

o   Fire products did really well, especially with the fire over North Carolina, really popped out

o   Need help sheets, some case studies

o   Change the naming convention of the RGB products

o   Wouldn’t hurt to spend an hour at the beginning on each week going through the RGB images

o   Check the sampling in AWIPS, make sure they are correct

• ·       GLM

o   Storms that spiked on the gridded data drew attention to storms, still hard to look at the point and be able to notice trends

o   Like the color table with the bright yellows and reds really differentiating the storms that needed to be watched

o   Excited because it’s going to cover some areas we don’t have current coverage for, and good for public safety

o   For training, open up with some case studies, capture the attention of the forecaster

o   Confusion about the difference between groups, events and flashes…need to create a good conceptual model…what is actually happening in the storm?

• ·       NUCAPS

o   Point soundings were useful, matched the environment

o   Gridded data weren’t coming across well in AWIPS, things were missing

o   Liked to look at the gridded data for higher areas of CAPE and the pick the point sounding near that area

o   Didn’t play with the cross sections, but think they will be valuable for forecasting

o   Need to improve latency

o   Needs to be a way to know which point was clicked, an identifier besides latitude and longitude

o   Since the MetOps come in sooner, they might be more helpful if they were operational

• ·       ProbSevere

o   Trends were so much more important than anything

o   ProbHail was really accurate

o   ProbWind seemed to really catch high wind values where it was most expected

o   Would like a way to look at threats as individual layers, maybe a four panel…since some days certain threats are more predominant than others

o   ProbTor wasn’t as good when storms morphed together into larger ProbSevere objects

o   Saw high azimuthal shear values, but ProbTor value was low

o   Like the contouring

-Holly Obermeier

Lightning activity increasing along an outflow NC Iowa

Lightning continues to increase along an outflow boundary across north central Iowa.

GLM Lightning

GLM gridded data seem to be missing in the southern sections of Clay and Yankton County into Cedar County. Why nothing on the gridded image when other networks are showing much more? -ams

ProbWind

Confirmation of high winds from Yankton ASOS (YKN) with ProbSvr of 98% and ProbWind of 94%. -ams

Outflow on 1min visible

Here's a look at how 1min updates and .5km resolution helps identify outflow from storms. Features that would not always be visible on in prior GOES data.

Yet another jump another SVR

Another SVR based on lightning jump and DVIL and probhail of 96 %.

Quick ProbSevere Capture

FSD radar of probsevere with 0% tornado at this point.

Supercell Splits

Seeing spuercell splits on the 1min GOES-16 is really helpful in spotting these splits quickly. Seeing them on radar but on the sandwich product is entirely different view of the process.

 

A storm split as it moved over an outflow boundary

A storm split as it moved across an outflow boundary.

Another lightning jump helped to issue a SVR

Another lightning jump and probhail of 96 percent helped to issue another SVR across OAX.

Clear Sky Mask

The default color curve for the Clear Sky Mask, Center CONUS, Derived porducts has black for both No Data and Clear. This needs to be changed.-ams

Lightning jump and high dvil values prompted to svr

First srv of the day across the OAX area based on lightning jump, cold cloup tops and dvil values.

Derived CAPE

Increasing levels of CAPE showing up on the derived GOES-16 product. CAPE values from the GOES data shows 1700-1900 in the central part of the CWA. This matched pretty well with the 18Z special sounding which was around 1500.

Sampling on VIS

Sampling on VIS now gives a percentage where on GOES 13/15 it gave a count. The count is frequently used on GFE tools for populating SKY grids. Either the GFE toolk that uses this needs to be updated or sampling needs to include count. -ams

NuCaps Compare - TOP

20Z TOP Sounding

1834Z NuCapps Sounding near TOP

For comparison. Steeper mid-levels in reality. NuCAPS misses the mid-level Capping inversions. TPW is pretty close to the Derived TPW from ABI.

ABI Cirrus Ch 4

Here is an example of thin cirrus that is more visible over PA than on the CH2 Red VIS image. Top image is the Ch4 -ams

pre storm enviroment

Starting off with a relatively stable environment, especially over the southern CWA. SGF and OAX soundings (TOP not available) showed with heating instability would increase. Will track the evolution of CAPE with the derived product. Favorable shear for supercell development.

Fire Temperature RGB

So outside of my operational area today but checked out the Fire Temperature RGB of a fire back in NC. Very cool and useful to see the the flare up of the fire. Even as wide view it stuck out.

NuCaps/MET OP sounding Locations thought

Generic comment.

Need some location ID on these sounding. Hard to remember which 'dot' one actually chose. Only one sounding at a time now but someday it may be more.

Reference in upper left of Lat/Lon isn't quite good enough.

Which dot is it?

Outflow/TPW/MetOPs A

Series of pictures showing the derived TPW picking up on increased moisture behind an outflow boundary. Lower dewpoints in the post outflow area (mid/upper 60s) vs. ahead of boundary (70-72). Soundings show the lower TPW in southern MO vs. higher TPW near Topeka (like the derived ABI). Actual numbers are little different but trends similar.

17Z TPW

 Springfield area.

Topeka

Obs/visible

EWP Week 2 Day 4

Participants will be working out of the Omaha, NE and Topeka, KS CWAs today.

-Holly Obermeier

ProbTor model on June 28, 2017

A shortwave at 500mb and a negatively tilted trough at 800mb with a strong jet helped force severe weather yesterday along and ahead of a cold front in Iowa and Minnesota, and along a warm front in Wisconsin.

Figure 1: Surface analysis Jun 28 2017, 2100Z

Participants in the GOES-R Proving Ground / HWT Experimental Warning Program were able to investigate the NOAA/CIMSS ProbTornado model for mainly the first time this week. The image toggle below (Figure 2) is a synopsis of ProbTor for the event, showing correspondence between ProbTor centroids (boxes, colored by probability), NWS warnings, and local storm reports (LSRs). Subjectively, elevated ProbTor values corresponded fairly well with NWS tornado warnings and reported tornadoes. There are of course misses (e.g., in northwest Wisconsin [not shown in Figure 2] and northwest Missouri. There are also false alarms (e.g., one storm in central Iowa north of Des Moines, and a couple in southern Wisconsin). These false alarms had severe wind and hail reports associated with them, but no tornado reports.

Forecasters using ProbTor should always keep interrogating base radar data, but we hope ProbTor output can help give forecasters a heads up on developing tornadic threats and add confidence to their warning decisions.

Figure 2: Accumulation of NWS severe weather warnings (red=tornado, orange=severe tstorm), reports from the SPC log (red=tornado, green=hail, blue=wind), and ProbTornado storm centroids > 5% (filled boxes).

I created post-mortem time series of ProbTor and some of its predictors for several storms. Figure 3 is for a storm that traveled east of Minneapolis/St. Paul, MN, into western Wisconsin. You can see the ProbTor value increase to > 50% at 21:22Z, owing to a sharp increase in 0-2km MRMS AzShear. Total lightning activity stayed fairly constant (20-30 fl/min), after an initial surge up to 40 fl/min. The environment was good (35 kts effective shear; 35 kts MeanWind 700-900mb; 2000 MLCAPE; 200 m2/s2 0-1km SRH), helping push the probabilities to 30-50% for about 40 minutes. Two tornado touchdowns were reported.

Figure 3: Time series for a tornadic storm east of Minneapolis/St. Paul, MN.

The next three time series show the trends for storms south and west of Des Moines, IA. This environment is characterized by higher effective shear and MLCAPE, but comparable MeanWind and 0-1km SRH to the storm in Figure 3. The storm portrayed in Figure 4 attained a 40% value 16 min before the first report of a touchdown. The value then dropped considerably, as the AzShear values diminished. Forecasters have noted the value of seeing trends in the probability and predictor values for ProbSevere and ProbTor in AWIPS-2, and we will make that a future priority. Forecasters should also note that there is no magic probability threshold -- storms with 80% ProbTor and 20% ProbTor will produce tornadoes, as well as false alarms. The environment the storm resides plays a large role in the overall probability, so forecasters are encouraged to interrogate the storm that "sticks out" from the rest (e.g., 80% ProbTor near storms with 30-40%; 30% ProbTor near storms with 0-10%). Anecdotally,  this seems to be true for many cases, but of course not every case.

Figure 4: Time series for a tornadic storm west of Des Moines, IA

The next two storms had higher MeanWind 700-900mb and AzShear values, spiking the ProbTor values into the 80-90% range. Large increases and decreases in ProbTor may represent storm cycling. We are beginning to look at storm path length, width, and duration, and their relation to ProbTor values.

Figure 5: Time series for a long-lived storm south of Des Moines, IA.

The storm in Figure 6 below attained ~90% ProbTor 9 minutes before the initial tornado report. It is uncertain how long the tornado lasted. The ProbTor decreased markedly down to 25%, before jumping back up to almost 80%, with no additional reports. The character of the rotation evident in the radial velocity (and thus MRMS AzShear products) should play a key role in warning decision making. For instance, perhaps the second spike in AzShear, while still strong, may have been broader than before, and did not require warning.

Figure 6: Time series for a tornadic storm southeast of Des Moines, IA. 

Future work on the ProbTor model will also include pinpointing areas of rotation and assigning separate probability values, as opposed to just contouring the entire storm, since this doesn't adequately identify where the threat is, especially in squall line or messy situations.

EWP Week 2 End of Day 3...Thoughts and Feedback

Participants ended their day working in the Des Moines, IA and Kansas City/Pleasant Hill, MO CWAs.  A line of supercells developed this afternoon and tracked southeastward across Iowa and northwest Missouri.

• ·       GOES-16 ABI Imagery and products

o   Fire products were useful, good for doing DSS, more effective for messaging and briefing

o   Help sheets are good, really key

o   RGBs will like be even more useful for general, daily forecasting

o   Saw -66 to -77 values in the 1 minute IR imagery, unreal

o   1 minute imagery was also useful to see areas where they was a lack of convergence, knew the development wasn’t going to continue along the boundary, good to see relative to the major areas of population

• ·       GLM

o   Using every day, love it.  Spikes in lightning were evident, have confidence with the lightning jump that you could warn on the storm right away…every tornadic storm had a lightning jump and a cooling top

o   Like the gridded GLM best overlaid with radar or MESH, not with satellite

o   Still would like a centroid, a way to calculate the lightning jump or a ProbSevere for lightning

o   Like the GLM combined product, tried the 1 minute vs the 5 minutes…not sure anything was gained by using the 1 minute

o   Would not release to local offices until the mapping is fixed

o   For training, going to need case studies, lots of concrete examples instead of job sheets.  Provide procedures.  Could even do live webinars.  Felt the training module for this project was too slow, equation/laws information were too in-depth  

• ·       NUCAPS

o   Like the gridded versions a lot, there is some real potential value there

o   Gridded data is really blocky

o   Latency is still an issue

o   Could give confidence to your forecast, or give you pause…maybe need to re-asses your forecast

o   If you aren’t near an upper air site, the data has use even if it’s not perfect

o   Make sure it makes sense with its location in the AWIPS menu, and provide a way to know when a satellite pass occurs…otherwise it’s easy to forget to look at the data

• ·       ProbSevere

o   Why isn’t ProbTor higher than 90% when there is a confirmed tornado?

o   Trends were good, helpful to get a warning out right away…especially on shift changes

o   Weird times when ProbTor would go up, but the AzShear would go down

-Holly Obermeier

ProbTor92%

EAX above

 DMX below

ABI and GLM helped again in taking a look

 

 Here's an example where the the sandwich product and lightning jump on the GLM grabbed our attention to look at a storm in our northern CWA. We were focused on the middle and lower part of our CWA so this was a great situation awareness tool today.

Moisture/Dry Line Retreat

Dryline/airmass retreat in western KS/OK/TX. Benjamin

 Channel Difference

Derived Wind pictures

Worlds greatest upper divergence in far southeast NE? Flow around updraft? Flow outside of anvil into central IA?

Benjamin

speed max through west central Nebraska help storm development and sustenance. Upper level derived winds on water vapor.

Highest TorProb

We saw the highest values for TorProb so far at 71% with a storms southwest of Des Moines, IA. We actually tor warn long before this values was reached but it still gave us confidence in the warning we issued. Funnel cloud reported with this storm.

ProbTor Large area

Same area of storm for  prob severe parameters over 2 states and 2 cwfas. Different areas of circulation with a combined 6% prob tor.

Benjamin

added another probsevere with 3 circulations...1 prob for the whole things. 80+ percent.

Gidded NUCAPS - spotty coverage

500MB temperature from gridded new caps. Spotty nature due to lack of good data. Some areas of green dots have no gridded data.

Does the gridded data have to be contoured?  What about just an array of color coated numbers or something. The contoured analysis gets kind of goofy looking at times.

Benjamin

GLM

Here's looking at various tornado warned storms many with confirmed tornadoes. Just with today's storms we could see a correlations to tornado warned storms and lightning spikes.