Another rise in mid-level moisture on AllSky Layered PW

Similar to MPX area yesterday, the 0.9-0.7 sigma level LPW product had an area ahead of the line of storms that had increasing moisture.

Similar Soundings

Modified NUCAPS sounding near ILX is pretty similar to KILX special sounding taken at 17Z!  MUCAPES both around 3000 and LI -9.
Values similar to AllSky at 18Z.




Those CAPE values near 2500 J/kg...also similar.
This similarity gives us some confidence in new forecasts, especially in clear sky regions out ahead in the AllSky data.
The forecast NUCAPS CAPE does not show much to the south of our line...and based on clear skies and warm conditions to the south would tend to lean away from this forecast.



Charley

Springfield Illinois Storms

Right now I'm analyzing the various new products to nowcast where and when storms will intensify. Currently I'm comparing ALLsky cape to the mesoanalysis from the spc. Right now the mesoanalysis is higher with cape compared to allsky. Over our area the it's cloudy so the it's taking data from the GFS.

A cell in our western counties ramped up very quickly while our computers were down. Prob severe immediately directed our eye to the cell. The probsevere lined  up with an uptick in vil values and the threat for damaging winds



I'm comparing the actual sounding to what's shown on nucaps, and allsky. Trying to see what's initializing the best. The actualy sounding shows 3000kj of cape around 17z.



Around the same time allsky shows a similar value of cape.



Here's what the modified and unmodified nucaps are showing.
I'm also looking at GLM products to see trends with convection. The combination of event density and glm minimum flash area help me to see the rapidly growing updrafts as well as cell that are producing hail. That's the case right now. My warned cell is producing penny size hail.

NUCAPS Forecast showing increasing CAPE in the south

The gridded NUCAPS forecast indicates higher CAPE values moving east into the southern IND area the next few hours. Will be expecting severe thunderstorms to develop later today.

ILX Upper-Air Sounding comparison to NUCAPS and Modified NUCAPS

Above is a special sounding released by the ILX office around 17z on June 5th, 2019. Below is the output for the NUCAPS and sequential Modified NUCAPS sounding from around the same time and as close to the same area as possible.



The NUCAPS pass pictured above was primarily in a cloud-free environment behind an old outflow boundary to its south and ahead of a developing line of convection to its north. Visually, it tended to underdue the CAPE values in the environment, especially in the low to mid levels.



The modified NUCAPS sounding (above) did show some skill in incorporating more accurate boundary layer conditions, which in turn, upped the CAPE values considerably (almost 2x in some cases). This brought the values into better agreement to the in-situ observation from NWS ILX with the exception of the SFC based CAPE which remained considerably underdone.
---------------------------------------------------------------------------------------------------Mountain Bone

NUCAPS Soundings indicating much higher CAPE than All-Sky values

The All-sky CAPE product has shown a pool of lower CAPE values (1200-1300), probably a result of earlier collapsed convection. However, values of CAPE farther down in the southern IND CWA are a little higher (1800-2200), as would be expected.  More interesting is the latest modified NUCAPS pass with soundings indicating much higher CAPE values on the order of 3500-4000 in the south and 1800-3500 elsewhere in the central and northern IND area. Based on this information, I'll be expecting to see convection flaring up in the south in the next hour or so.

ILX GLM Case

(Top Left): GLM Event Density w/ ENTLN Lightning Data; (Top Right): MRMS -10C with ENTLN overlayed; (Bottom Left): GLM Minimum Flash Area; (Bottom Right): GLM Total Optical Energy

Had a unique opportunity to watch a line of strong to eventually severe storms ignite and strengthen rapidly along an old outflow boundary this afternoon using GLM data. It was interesting using the above 4 panel display to not only witness the ignition, but also the strengthening of each sequential cell along the line. By utilizing the GLM Minimum Flash Area (Bottom left) 1 minute imagery in a loop, we were able to sample the early-onset updraft core strengthening of each sequential cell along said line, and watch the event density jump up in accordance. It was also interesting to utilize the Prob-severe lightning jump data in time-series format to watch in a real-time basis. Suggested best practice would be to make these 4-panel layouts available for events like this.

ILX All_Layer CAPE Comparison

Taking a look at a quick comparison example of when the model fill-in of the All_Sky CAPE product may not be the best solution. In this example, an ongoing MCS was diving south through north central IL earlier this morning before it dissipated rapidly over the central part of the state. The GFS model struggled depicting the rapid de-escalation of said storms, and attempted to stabilize much of the ILX CWA in its wake. Unfortunately, this led to quite the gradient between areas where clouds prevented in-situ satellite observations to be utilized in the All_Sky CAPE product. Taking a look at the SPC Mesoanalysis (RAP) output in image 2 for comparison, the more accurate CAPE values across eastern IL should be closer to the 2500 - 3000 J/KG range while the ALL_Sky CAPE layer (Image 1) is showing 1000 - 1500 J/KG tops. A suggested best practice to overcome this discrepancy is to  include the AllSkyLAP Layer Cloud Type Image underneath any AllSkyLAP product so you can easily depict what is sensor derived and/or model output.

---------------------------------------------------------------------------------------------------Mountain Bone

ProbSevere a quick guide to hazardous weather

While getting set up on D2D, storms are entering the IND area from the NW. ProbSevere is a great tool for a quick analysis of the primary concerns arising from this line of storms and gives a great starting point for how to further interrogate the system for warning issuance.

AllSky CAPE high in one place low in another

cells persisting in far western CWA has high CAPE on latest AllSky product.  However, the line of storms that moved through the middle of the CWA is now in the eastern part and into ARX's area.  Line continues to look severe, with AWOS in northwest ARX gusting to 52 knots, but CAPE not as high.

CHARLEY