AllSky H9 PW Shows Dryline

The AllSky H9 PW product showed good advancement of the dryline into West Texas today. Convection quickly developed as the dryline advanced into the Panhandle.

NUCAPS Lapse Rates

As an operational forecaster, I like to compare model output, real-time obs, and any additional derived data. This image from the NUCAPES H85-H5 Lapse Rate can potentially help boost one's confidence in particular synoptic situations. For example, suppose you were expecting a dryline to emerge east across W Texas, but guidance indicated otherwise and sfc METARS were unavailable, using the NUCAPS Lapse Rate products can help determine the location of the dryline (for this particular setup). In this image,  values reflect the drier air advancing east leading to steeper lapse rates.

Used GLM to Issue SVR

I'd been watching a multicellular cluster that was trailing a leading supercell to the north of Amarillo. Had been waiting on issuing due to ProbSevere and Mesh levels, but GLM FED increased and reflectivity / VIL /core height all responded so I issued a warning at about 2040Z

19Z NUCAPS Comparison with METAR at LUB

Modified NUCAPS soundings taken at 19Z became available in AWIPS and was noticed around 2030 UTC. The One taken near Lubbock was flagged as a Successful. I wanted to compare the NUCAPS sounding withe the nearby 19Z METAR observation and found the METAR measured temp/dew observations of 77/61 where the NUCAPS sounding at the same time had surface measurement of 69/58. The difference between the surface temperature observations for a modified sounding was concerning.



#ProtectAndDissipate

Big, Bad, Flash or Bad Big Flash

Everything was chugging along great with the GLM and the storms around Amarillo this afternoon as this image from 19:54 shows (TL - Flash Extent Density 5-minute w/ 1-minute update with Vaisala GLD Data overlayed, TR - Minimum Flash Area with ENI Total Lightning overlayed, BL - Total Optical Energy with Vaisala NLDN overlayed, BR - IR/VIS Sandwich):



But then the next set of data arrives at 19:55:

So, that big white area showed up which is a 2918 km² area flash.  WOW.  THAT. IS. HUGE.  But the question now becomes is that correct or not?  Taking into account parallax and the data from the ground-based networks shows that there was electrical activity in the general area.  However, it isn't in the area that would line up with the parallax; the ground-based network data should be closer to the southeastern area of the flash.  Also of interest is that there is no Flash Extent Density associated with the large flash but there is an associated area of Total Optical Energy.
One thing we are tossing around here is the possibility of a cloud reflection; here is the 1-minute visible mesoscale scan with the big flashes overlayed:



If there was indeed a flash at this time, the optical energy could have reflected from the originating area off the anvil, and then reflected back off the low clouds around the updraft to the GLM instrument.  However, the fact that there isn't any data associated with this flash in Flash Extent Density is concerning.  Needless to say, the lightning scientists here are all going "Hmmmmmmm...."

-Dusty

GOES 17 May Have Better Angle of TX S Plains Storms

Due to the location of GOES 17 and GOES 16 , forecasters may want to consider the satellite's angle of view for convection. In this example, GOES 17 has a better "viewing angle" into developing convection across west Texas.  Optical brightness has been brighter than GOES 16 and a better output of Extent Density.

ProbSevere Progression with intensifying storm

I like seeing the progression of the storm on the ProbSevere page, showing the trends of developing convection. You can see how the increases of ProbHail and ProbWind parallel certain parameters like MESH, VIL, and Flash Rate parameters.  It's also interesting to see what's not being utilized or loaded into the page such as Sat Growth Rate.





With some MRMS data being loaded into the ProbSVR model, one possible addition to the parameters could be Vertically Integrated Ice (VII) vs VIL. Have found in operations to be a very good indication for strong updrafts above the FZL. Hail and Wet Downbursts have been correlated with very high values of VII (above 25-50 kg*m^-2).

#ProtectAndDissipate

Modified NUCAPS Representing boundary layer well

NUCAPS modified sounding doing a good job of representing the boundary layer in the near storm environment in the AMA CWA. Green dot ahead of cell in middle of image was selection point for provided sounding.





icafunnel

Dryline Progression with AllSkyLAP

Noticed a glitchy progression in the AllSkyLAPs 900mb PWATs. Believe this might be from an updating GFS guidance, but this also occurred at a time when the areas west of the LUB CWA were transitioning from about half Cloudy, half GFS to mostly GFS. However, the updated location of the dryline was a closer approximation of the location of the dryline at the given time.



#ProtectAndDissipate

5-Minute with 1-Minute vs. 1-Minute GLM Min Flash Area

So, the first thing looking at today is the best way to display Minimum Flash Area.  This is a nice addition to the Flash Area products and seems to have some utility in displaying the state of convective growth.  As a reminder, smaller flashes are usually indicative of new or strengthening convection while larger flashes are mature/decaying/sustaining stages of convection.  This will come in handy with a lot of convection to see which cores may be the strongest in any given area.
The problem is the best way to view this information; the 5-minute with 1-minute updates seems to have worked well in the past for most of the GLM data but seems to cause some problems with the Minimum Flash Area.  Case in point, here is a 4-panel with the 5-minute/1-minute update from the Texas Panhandle north of Amarillo (TL - Flash Extent Density, TR - Minimum Flash Area, BL - Total Optical Energy, BR - empty; note, non-default color tables on the top row!):



Wow!  That's a pretty large area of small flashes (purple).  BUT, it's a total from the last 5-minutes so storms could have moved, strengthened, weakened, dissipated, etc. in that time.  What does the "regular" 1-minute plot look like?



Huh?  Where did all the small flashes go?  Well, the small flashes (purple) in this case are likely where the GLM is seeing the strongest updates in the last minute, not the last 5 minutes.
Something to consider when looking at rapidly developing convection, storms that are moving fast, or storms that are pulsing with rapid time intervals; the 5-min with 1-min update can mask important details when it comes to storm electrification!

-Dusty