Week 4 Summary and Feedback

Below is feedback from our final, week 4 weekly debrief session, along with a photo of the week 4 participants.

This marks the conclusion of the GOES-R portion of the 2014 HWT Spring Experiment!


- Bill Line, SPC/HWT Satellite Liaison

Simulated Satellite Imagery:
- It’s great to use the imagery to evaluate model performance.
- Had issues with burning off low stratus too early, leading to errors with heating during the day and errors of convection timing
- Do you see simulated model imagery being useful in forecast environment; would you like to see this data with other high res models?
    o All say yes, it is useful and would like to see it with other models (hrrr, etc)
    o Higher res models might pick up more discrete features things
 - Easy ways to pick up on errors in the model

Nearcast
- I used it mainly for ted and pw, it almost shows this better then anything I have in my office
- Nice to have in awips to overlay other things
- Helpful to show where boundaries will move, areas that are moistening
- Best as a precursor, ~3 hours prior to ci mostly
- I like the fact that you could really key in on boundaries, and I saw convection go there.
- Even subtle gradients up in high plains, small increases in ted, see showers pop up
- In Raleigh, having a tool that may easily show boundaries, esp in spring and summer, it could help
- I see more utility in theta-e and ted than in the PW field
- Calibration issue, we are used to looking at CAPE and LI. What does the ted values mean? Is there a way to do this?
- Its real-world information, which is good
- Overlayed forcing parameters on it.

Ci
- Didn’t increase my confidence as much as I had hoped
- One cell I tracked for a while in Huntsville area, had pretty high value, that did go up and eventually became strong
- Get rid of lower values

Probsevere
- This is especially useful for more slowly developing convection. Storms that look the same may have different probs, pointing out which storms are actually more threatening,
- Not as useful when convection is rapidly developing. The 1-2 scan lag hurts
- Good as a confirmation tool even for mature convection
- Good for slowly developing storms, detects hail well, poor with wind, not sure with tors. Prob severe hail may be better name. Rapidly growing convection, it wasn’t as useful with lag (1 volume scan), which hurt.
- Broadcaster – I really enjoyed this product. I am doing a lot during a day, especially severe day, it pinpointed where I should look. Same with CI
- Right now, as a regional SA tool, storms coming in from neighboring CWA, would be good to watch. Also for updating warnings.
- Column velocity to determine wind threat,
- Seems like product that has room to do some interesting things.
- with prob severe/hail/wind/tor, have a 4 panel, with total severe and 3 threats. Different parameter underlaid each

Overshooting Tops
- Broadcaster – really useful for me, in busy environment. I can speak for every broadcaster, we’d all love to have this product.
- More utility at night than during the day
- Helpful to CWSU cause I'm looking at a much larger area

Tracking tool
- This trend information is beneficial to have.
- Probably best for warning coordinator, or for research purposes. It is high maintenance, takes a lot of work to use

Lightning
- Broadcaster – lightning is especially useful for me, the chopper folks are constantly asking me where there is lightning to decide whether it is safe for them or not
- Most useful for rapidly developing convection
- Any time a jump occurred on a storm, the dBz’s would spike soon after
- I think it is everybody’s favorite thing, the lightning
- Most helpful for a warning operator, everything else was more SA.
     o Mostly because we had information every minute.
     o Getting additional info while we are waiting for next volume scan
- It impacted my warning decision making process.
- Especially useful in rapidly developing convection
- Broadcaster – lightning is very important even if it isn’t severe
- I wish I had more time to look at it.
- Training for lightning is not that good, to understand more why/how this is working, would be helpful. Why in certain environments and situations would it not work so well. But why better in others
   o Explain what is going in and why it is working

Broadcaster – from this perspective, most of the products demonstrated make it easier for him to do his job, because he can easily spot where a new storm is coming up in busy situations, where lightning is increasing. It helps make things easier for everyone at station.

CWSU – CI and OTD would be most useful for me, covering a broad forecast area. OTD quickly shows me where the strongest updrafts are, and ci highlights where convection is initiating or most likely to initiate in the near future. Also, lightning data is valuable for me.

General – be cautious of data overload. Products have to quickly prove their worth and utility in operations. Some products might be more useful for a warning coordinator, while lightning and maybe prob severe could be helpful for radar operator

Overall
- 1pm briefings from EFP, is there a reason for us to be in on that. A lot of it was not important
- Even from the briefings, I had no idea what was going on. It seemed more like a debrief for themselves. It had no application to us, it was geared to the efp
- I could have better spent my time making myself aware of the meeting.
- Schedule our debriefing during that, and maybe have it earlier (noon)?
- Since a lot is pre convective environment, we should come in at 9 or 10 to start.
- To be able to look at these products with other convective modes would be useful too.
- Broadcaster – recommend others to get with local wfo and get a couple hours in front of awips. Simuawips helped quite a bit.
     o This is most fascinating week of science I've had in a while.
     o Very much against working with just broadcasters in the hwt, found it very beneficial to be here with nws mets.
- All forecasters gained, learned from each others unique perspectives. Against segregated experiments.

Blog 2 Day 4 on 5 June

Have switched to the HUN CWA as of 1930Z.

Discussion of NSSL WRF sim sat with IR and water vapor.

Large MCS to the NW of the CWA moving into it. The NSSL WRF shows the MCS but is far less robust on the eastern end of it than is apparent in the IR imagery. Also strong cirrus shield is present east of the MCS which is not present in the NSSL WRF. This will have obvious impacts on model performance because of insolation issues etc.

Over the Carolinas we have some convection developing ahead of a surface cold front.. the NSSL WRF is to robust on the convection esp in KGSP area. Although it is doing quite well but a bit fast (by 100km) over the outer banks of NC.

Talking with KP about carolinas and the spatial errors may be due to model limitations on depicting the Appalachians.

DSatterfield & KP

Simulated Satellite – Thursday

Started off the day by examining the Simulated Satellite products.  Overall – they provided a good starting point over CO.  It showed the stratus burning off in eastern CO in about the right time.  Plus – CI initiates around 18-19z which is evident in the actual satellite obs.  Thus – the NSSL WRF should provide an accurate depiction of overall convective evolution.

18z Top – 19z Bottom

Daily Summary: Week 4, Day 3 (4 June 2014)

Today, we operated in 4 county warning areas:

Team 1 (Fowle & Anderson)

Louisville, KY
Springfield, MO
Cheyenne, WY
Team 2 (Pelczynski & Satterfield)

Boulder, CO
Early in the day, it appeared that the greatest severe threat would exist in the MS/OH valley region.  Additionally, there were enough breaks in the high-level clouds to allow for use of the GOES-R satellite products.  However, as the day progressed, it became apparent that the region would not destabilize as much, so we moved Team 1 to Springfield, MO (based on a favorable mesoscale discussion).  As it turns out, the capping inversion would hold over that area.  Thus, we moved Team 1 to Cheyenne, WY – hoping that we could catch some lightning data from the LMA in Denver.  A few marginally-severe storms did develop.

Team 2 remained in Boulder all day.  There, they used the GOES-R products extensively, including the NearCast, UAH CI, Probability of Severe, and lightning data.  Several severe storms developed, though only one severe report was officially logged (for a landspout tornado).

-G. Garfield
Week 4 Coordinator

*** Day 3 Feedback (Bill Line): ***

Simulated Satellite Imagery
- Spot on yesterday. As far as overall timing and development, it was really good. The fact that it picked up on little features early gave me confidence in the rest of the forecast
- Not as good in Missouri area.
- Burning off stratus too quickly seems to be a recurring issue with the model

Nearcast:
- I liked it yesterday, particularly because as we sat down there was convection getting going, related to theta-e diff gradients, you could predict where they would move based on the nearcast forecast.
- We looked at it for a good 2 hours
- Theta-e values were pegging where it finally developed in far northwestern NE

Goes-r CI
- Looked at in with the other products in the 4 panel
- In Kentucky, it was bubbly, weak CIN,  a lot of low values that jumped around, noisy field, didn't see values over 60%
- It triggered on a few but we were already on them.
- Might be better for larger areas of monitoring (larger than CWA)

Prob severe
- Sometimes it is a nice confirmation of what we already concluded
- With rapidly developing convection, storms went severe within a few scans, prob severe lag kind of hurt it
- With gradually developing storms, it may be more of a confidence builder to issue a warning
- In broadcast world, this is valuable in pinpointing a storm to look at
- One went 16 to 60 in one scan, making me look at the storm
- In Louisville, a lot were hanging in low range, it told us what environment would be like that day, very low end, bubbly stuff
- The values it showed us were helpful (predictors) to see
- Satellite ingest made a huge difference (with satellite data compared to without)
- Tells us what is the trend of the day, perculating stuff, or fast growing
- With trends it was somewhat helpful with dissipating storms, you could see that chances of it being severe were becoming less. Caused me to look at it more
- There was a lag between when I issued a warning based on prob severe and when NWS finally issued

overshooting tops
- I can see, with mcs’s, having this info is useful, you can see where stronger storms are in a complex, you have a long line, key in on these areas.

Pglm and LJ:
- I could see reflectivity increase 15 to 20 min after lightning jumped up. Tracking tool helped me see this. I think both of them together is valuable
- The lightning jumps led to me quickly issue a warning with rapidly developing storm in boulder.
- I used just lightning data to issue warnings,
- Using FED in conjunction with LJ was a red flag that storm was rapidly increasing in strength
- I thought it was really good yesterday
- LJ- I find it useful and like being able to see when it jumps,
- Option for max LJ over last 5 mins would be great. Still update every minute though. (Running max). So that I don’t miss an LJ in the rapidly updating product.

Tracking Tool
- I like the idea and concept of it, compare trends in fields and different storms. But there are a lot of problems
- Looks like I have to load all products first, then load  tool
- I crashed my system
- Very handy with lightning and reflectivity
- May be more useful to look back at archive data. Research tool
- In real time, it takes too long to work, you don’t have that much time. Maybe just the warning coordinator
- Its not telling you a lot different than what you can see

One last satellite comparison and forecast

The first two images showing the simulated satellite imagery (left) and the real-time satellite imagery (right) reflect the overly rambunctious coverage in the simulated imagery earlier in the day (1st image), however the latest images (2nd image) shows the simulated imagery underestimating the intensity with the storm in CO. Looking at the last two images, forecast imagery for 03Z and 06Z, they imply that perhaps the simulation is just lagging behind with generating the intense storms in eastern CO. Based on this simulation, and the fact that it has performed well all day, I would expect additional storms to develop in eastern CO/western KS over the next several hours…moving east thereafter.

-KP

Simulated Satellite – Location #3 – CYS

Looked at the simulated satellite imagery over the CYS domain beginning at 2300UTC.  Overall – a pretty good depiction of the convective evolution in this location – although there appears to be storms too far east over the NE panhandle.  Expect storms to move into that area – but the model was probably a couple hours too quick.

Sim Satellite at 2300 UTC:

HWT Wed 4 June blog 4 – Synthetic Sat (NSSL WRF) Evaluation

Evaluating the NSSL WRF sim sate with IR window and Radar over Colorado. While NSSL WRF is as usual overly robust, the model did show a cloud boundary over SE Colorado that is very present in GOES IR. This boundary is transverse to a theta E diff Boundary and up-slope flow. We expected some convection here (out of our CWA today) and there is some development along the NM/CO border. The NSSL WRF also shows the convection (albeit weak) east of KPUB that we are monitoring. I continue to believe the synthetic NSSL WRF imagery to be very valuable in not only evaluating model performance but as an important tool in locating areas of concern.

D Satterfield
KP

Showers going up in a favored area

This image shows the convection trying to get going in an area along a dewpoint gradient, denoted by the dryline symbol, and in the vicinity of the nearcast gradient in theta-e difference. This is the area we were focusing on based on both the nearcast forecast and the simulated IR imagery from earlier. Expect this to continue to be a favored area…with a potential shift eastward throughout the afternoon.

-KP

-D. Satterfield

Wed – Simulated Satellite

Started my analysis with a quick look at the simulated satellite products.  Both the IR/WV fields seem to have a relative handle on the large scale features.  However – the NSSL WRF appeared to develop vigorous CI around 18Z over central Indiana – which was not evident in the observed satellite data.

In this instance – the NSSL WRF could basically be discounted for at least the next couple hours.

An arguement for increased output frequency in WRF Simulated IR

The top two images show the change in forecast IR satellite output over the course of an hour. There is a good amount of enhancement during that time and, as shown in the third image at the bottom of the page, there are some enhanced cloud features with CI values in the 40-60 percent range. This would be a case (where convective initiation is likely within the hour) where having 15 minute WRF simulated IR imagery would be helpful.

-KP

HWT Wed 4 June blog 1

Notices on the NSSL WRF synthetic images that the model erodes low cloud over the high plains much to quickly. This seems to be more noticeable in KS and NB and it does a better job in the high plains of CO. Obviously this kind of error will induce spatial and temporal errors in the wrf forecast.

Kathleen and D Satterfeld

Daily Summary: Week 4, Day 2 (3 June 2014)

A strong short-wave trough moved through the Central Great Plains, generating severe thunderstorms in a strongly unstable and sheared environment.  During the event, we operated in two CWAs: Hastings and North Platte.  Forecasters Pelczynski and Anderson operated in Hastings; forecasters Fowle and Satterfield operated in North Platte.

When we started operations, convection had already begun in NC Nebraska, and it began to grow upscale as the sytem moved toward Omaha.  Further west, convective initiation held off for some time, before multiple storms fired along the warm front that stretched across central Nebraska.  A supercell near Ord, Nebraska became tornadic, and produced multiple tornadoes along its path just south of Omaha.

However, as the cold pool north of the warm front strengthened, it became increasingly clear that a major tornado event would not occur.  At the time of this writing, however, it appears that a significant wind event may still occur in eastern Nebraska into southern Iowa / northern Missouri (per the SPC high risk).

-G. Garfield
Week 4 Coordinator

Feedback (BL)

Simulated Satellite Imagery
- A+ on that. Model missed convection because it had a cirrus shield that wasn't actually there. So the model  likely developed convection late because of this.
- Gives me confidence in the model. from a big picture standpoint, I think there is some utility there for forecasters
- Even if it didn't do the best, its still important information
- Suggestion – fade in out reflectivity

NearCast
- I liked the theta-e diff and pw plots. Good for getting idea where you may start seeing convection get going, particularly where there were strong gradients. Using current vis with nearcast forecast, I looked for where would fields interact with boundaries in the near future.
- Gradients are helpful, qualitative area where you want to investigate further.
- Even with data dropouts, you can infer.
- Its good in the pre-convective environment, going into event. Once warnings get going, kinda stop viewing it

GOES-R CI
- For us, there was a lot of cloud obscuration, from high cirrus, for storms that were obviously going
- There were areas where you could see ci increasing for successive volume scans where showers developed
- It did pretty good in showing areas along line that would develop
- But doesn't give much info on whether developing convection will become severe
- We use ctc in our office, I find that to be more useful. You don’t get a lot of noise, it just gives you cells that are growing the quickest. It provides what storms are growing, and gives quantitative value of that developmental rate. That to me is much more useful than ci product. It doesn't hit every storm, but I like that quantitative info it gives. We pay attention to the -10, -20 -30 thresholds.
- Broadcaster world very much use this – something that tells you where to pay attention is valuable. Every broadcaster would like to have the ci.

ProbSevere
- I thought it was useful – times when you had big jumps up and down, which is good to know. Good safety net, gives you clues on which storms you need to pay attention to. A little more calibration on some of the thresholds might be needed. Seems like its more of a hail predictor.
- For wind – temp-dew point depressions, sub cloud evaporation. Which will be wind producers.
- For situational awareness, if I'm on air, prob severe would be very helpful for me (broadcaster), esp if I am only one in at the time. If I can see quick prob severe on another cell, it would lead me to look at it
- Color curve, I struggled with near 10% and 40%, they looked similar.
- Once it becomes severe, it doesn't do you much good anymore, there are a lot of other products that could tell me its decreasing, etc. Once its mature or producing severe, maybe make it a different color or something
- For a colorblind person, it could be difficult. perhaps get thicker with lines as you go up (moreso than is already done).

OTD
- I think its most useful to see when tops are dying.

- I think with 5 or 1 minute data, this would be more useful, especially at night

2100Z High Risk Day 3 June. NSSL WRF Comments

NSSL WRF has some 2-3 hour temporal errors over WEST NB this afternoon. The reason seems to be slow heating due to a model forecast showing a thick cirrus shield over the area. There was a minor shield of cirrus but it moved east and vis satellite showed strong heating by late morning in the area. Convection developed well ahead of  the NSSL WRF forecast due this cirrus impacting the heating and thus the forecast going forward. A great example of using a close analysis of synthetic satellite imagery to adjust  and evaluate model output.

images below from 14 Z and 23Z 23Z on top.

D. Satterfield from WBOC Salisbury,MD

satellite comparison 19z

Looking at a comparison of simulated and actual satellite images at 19z shows that the model is too aggressive with convection, or at least clouds in south central NE. It did not at all capture the ongoing supercell in far northern NE.

jca

First impressions Day One HWT

Being from the broadcast side of things, my familiarity with AWIPS is low, but the HWT folks here have given me a quick course and I am getting quickly used to setting things up for the week ahead.

From the pre-HWTB training moduels, I am very interested in the NSSL WRF sythentic satellite imagery (GOES R PG), the Prob Severe Model and the Convec. Initiation/LAPS.

I already use synthetic imagery from a 4km model (RPM run by WSI in Boston) and have found that it is very good for quickly determining how well the model is performing on a daily bases. You can easily spot errors in convection/cloud precip etc. I have also frequently found that the model will do well but has temporal errors of up to 120 mins. Will I see the see the same thing with the NSSL WRF Simulated imagery this week?? Time will tell and I will look for it. My first impressions today are that it is very similar to my previous experience and will be quite valuable as a model diagnostic tool.

Lightning jump is another thing I will be looking at hard because I have had recent experience in seeing this (albeit only on CG data) with a tornadic super-cell in Delaware that produced an EF1.

Lastly the CIMMS theta E difference seems to have high potential to improve temporal and spatial forecasts of convection. The case studies I looked at during the pre-HWT training were impressive. Am hoping to see it in action this week. Today we are looking at some high theta e diff moving into Southern KS this Monday afternoon. Will see if the convection goes along the boundary we have id’d near Osage Cty Okla.



Dan Satterfield
WBOC TV Salisbury,MD

WEEK 3 FEEDBACK (including Day 4)

Day 1, 2 and 3 Feedback is included in the respective Daily Summery posts. This post includes feedback from the Week 3 final debrief.

-Bill Line

Simulated Satellite Imagery

- Maybe for last week, show nssl wrf reflectivity as well and show things that you can see in the synthetic sat imagery that you cant in reflectivity

- I like it, I used it every day. 

- Model issues

    o It was off with strength of storm, position, timing sometimes. 

    o Cirrus and low clouds often out

- The technique is great, to be able to visualize what the satellite would look like if this model were to pan out. I use nam in my office. It is nice to show low clouds and cirrus shields in the model. if you come out on day shift and it is showing supercells later in day, I would look at early part of forecast to give me more or less confidence in later forecast

NearCast

- I think it is a benefit to have

- I think at the very least it helped to visualize moisture and instability very well

- How to use it from day to day changed. First day, storms initiated as theta-e tongue came in. Next day, theta-e was feeding directly into storm, and it popped up. Next over DC, entire theta-e field, storms followed along with the movement of theta-e

- Go to product between warnings, see what the environment is. Continues to tell you if storm is gonna be in field where it continues to explode, or will it move out of it. 

- I can see it being useful as I come in in morning, it fills gap in sounding data, gives you idea of scope of convective instability.

- Its observed data so I really like it

- I though the model forecasts did well too when there wasn’t missing data.

- Forecasters agreed it would be neat to see winds plotted

GOES-R CI

- I agree it would be very useful in non-severe situations.

- It had its hits and misses

- If doing esta update, might be good to say precip chances might be increased in a certain region

- I couldn't get a handle on a threshold where this is when convection would go. I couldn't rely on it

- I think it would work for SPC mesoscale forecaster

- Instead of individual colors for each object, highlight a general area of interest where convection is more likely to go.

- It is a good situational awareness tool

- Neighborhood approach, larger spatial probabilities might be a good idea. Instead of showing probs for each individual object

Prob Severe

- I like it: I used it every day. The trends were very useful. I liked seeing the data when I sampled (I looked at trends in the numbers). It helped me to zone in on certain storms (broadcaster)

- Yesterday I used it fairly heavily.  Storms moving form KY to TN, what happened was because it was multicellular, there was an adjacent storm that prob severe latched on to, and the product took over that other cell too. So it was then difficult to key in on that particular storm. I wanted to increase lead time, but I wasn't able to in this particular instance. There was some lag time too

- A way to have a sub-scale tracking to make sure to track individual cells to try alleviate merge issue

- Would you use in your office: All yes

- It at least brings your attention to storms to watch

- You start with all tilts. From a spatial awareness perspective. Id be worried about new forecasters getting lazy, relying on these derived products. You still need to get them used to using the base products. Similar to other products.

- But I think it could be treated as any other algorithm I don’t think that ^ is a problem

- There have been times im interrogating a storm in base data, this algorithm would point out a storm that I should look at. It catches things the human would miss.

- What would you like to see added: you don’t want it to get too cluttered. I like the compactness of it. Other environmental attributes could  help that would tell you what type of severe. DCAPE

- I would like to see effective SRH added. 

- Would you like to see probs of individual hazards: all yes

- I could envision a 4 panel. Over all prob severe, prob tor, prob wind, prob hail.

    o And have different fields under each

OTD

- I really tried to use it yesterday. One of limitations was the 15-30 min updates. It wasn't terribly useful in the hot seat. Might be better for mesoscale forecaster.

- I see this being most used in places where you don’t have radar. Oceans, aviation even more so (route planes around this). 

- I see it being much more useful, viable with higher temperal, spatial resolution. (super rapid scan with goes-r)

PGLM and LJ

- It was very useful in Denver day. Seeing total lightning and LJ

- I could see myself using it in warning operations. Monitoring health of updraft

- Pulse. In OK you see storms pulsing. Total lightning showed this. within 10-30 min I can guarantee something will happened

- In W Texas, severe winds were reported. Cell merger > LJ > wind

- LJ twice in a row, prob severe was trending up, I warned, big jump on warning

- Because it is one minute data, I was able to see jump before next radar scan

- I view storms as how much energy they can output, lightning kind of gauges how much energy is in the storm > hail, wind, etc. Updraft > more ice, static electricity, lightning.

- As a broadcaster, it would be nice to have total lightning, because it shows more than just CG.

- LJ display: I was fine with it, I was fine with sigma jumps

Tracking Tool

- I think it has a lot of potential, I was excited to use it, but it dissipated me.

- I like that you have a graph that pops up. I prefer it to be side by side

- If you close it, it would be nice to be able to pull the box back up

- I would like the ability to take the box out, I like screen real estate. 

- I think this type of tool (to show meteogram) is useful. I like the circles. I think it would be useful to track many different fields

- I prefer when you clear, for box to go away.

- In warning mode, I could see myself using this. 

- Its awesome to be able to use the individual points without having to move the whole track

SRSOR

- Do you see it having an impact on my decision making process (4 yes’s).

- Watching area, I could see growth in the 1-minute data, it helped to gain more confidence, I need to pay attention to this area

- In office, many times waiting 15 minutes for next scan. With 1 minute data, you can see convective attempts, failures, dead anvils.

- Would you be disappointed if goes-r was launched and we did not get 1-minute data? (all yes’s)

Simulated Satellite this afternoon

When looking back at Simulated Satellite today and seeing how it performed, it actually did very well.  It was on point with the timing of initiation of convection and the location of the start of the storm as well as how they moved.  The only thing it really lacked was the strength of the storm.  I would use this product for forecasting purposes! ~Vollmar

Starting the day in OHX

Since convection has not fired up yet in the Tennessee/Ohio Valleys, I was able to spend some time analyzing the pre-storm environment with the products we’re testing this week. The first on the list is the NSSL-WRF simulated IR/WV satellite product; I pulled up a four-panel with simulated on the left and actual on the right (below). As of ~1845Z-19Z, the simulated imagery was depicting isolated convection across southern KY and middle TN too soon but not necessarily entirely inaccurate. It is accurately honing in on the cloud cluster centered over IN-IL-IA/MO border, albeit overdoing the coverage and coolness of the cloud temps, as has been observed all this week. Interestingly, it is not picking up on the cirrus overspreading the Ohio Valley and into TN. Accounting for all of this, I can adjust accordingly and remain confident in using this product to develop a mesoscale forecast.

Moving to the next item on the list, I pulled up a four-panel of the NearCast analysis products with 500mb theta-e in the top left, 780mb theta-e in the bottom left, theta-e difference in the top right, and 900-700mb PW in the bottom right (below). A surge of mid-level instability can be seen diving into TN and is also evident in the difference product with the gradient diagonally stretched from the NW corner of TN to the SE corner. PW values/moisture surge matches with where storms are quickly firing up in western and south-central KY. When analysis data is available for these NearCast products, I really like to use these to diagnose and forecast.



Next, I loaded the same four-panel with the NearCast forecast and took a screen shot of the 2-hour forecast (21Z, below). Unfortunately, missing data over the region of interest exists with the 500mb theta-e and theta-e difference products. However, I can still see the lower-level instability and moisture axis draped across western KY into TN in the 780mb theta-e and 900-700mb PW, respectively. Given the success of these products so far, I have good confidence in utilizing the forecasts to accurately predict where the greatest threat will be, given other atmospheric conditions line up for convection as well.



Looking at GOES-14 SRSOR vis imagery and overlaying the CI product, a 60% probability popped up in western KY (below) and within a half hour, storms developed in the vicinity. There was a false alarm 60% probability just to the west of Paducah, KY, probably due to the thin cirrus streaming over a CU field there. In OHX’s CWA, no reliable indications of convective initiation has appeared yet. As for the SRSOR product, I am once again very pleased to have this data available to more accurately assess and see the evolution of the regional atmosphere.



Below, I overlaid OTD on IR SRSOR imagery and thus far, no detections.



~Linda

Simulated Satellite WRF. Cirrus/Insolation issues leading to convection.

Decided to through in a pre-enviornment blog about convection over southern West Virginia and far southwestern Virginia. In this case a plume of cirrus/ cirro-stratus is not showing up in the WRF. Normally that would be rather benign.  However in this case that cirrus is blocking just  enough isolation to prevent storm development over both areas which is keeping storms from popping and having the time to hit the equilibrium level.

Grant H.

Simulated Satellite Vs. IR Sat

I was analyzing the NSSL-WRF simulated satellite versus the actual IR satellite and as you can see it is missing the cirrus cloud deck over the VA peninsula and eastern VA.  It also is missing the cirrus cloud deck over eastern West VA which may hamper or at least slow convection start today.



In one hour it is trying to already form storms over parts that are covered by the cirrus blanket so I wonder if this won’t happen since it hasn’t accounted for it. We shall see. ~ Vollmar