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Severe WX April 1-2 (overnight) Severe Weather Event

Sooo...in the small lull we have, I'm going to start posting the output for my WRF-ARW's latest run. This is centered on Jonesboro, Arkansas and runs through Friday. I may post in a couple of segments since the model is still winding down and not quite finished yet. It's a 3 km resolution, so it should resolve convection and such.


Here's SBCAPE that shows the expected repeated rounds of instability that will ravage the area. This currently goes through hour 80 from 06z initialization time. (Some of the later graphics will go past hour 80, but since I started the app and 80 was the max at the time, future hours beyond 80 will just show ?, but you can still see the "Valid Forecast" time and such.)

test455.gif


Here's the STP (fixed layer), using the same formula as the SPC in the mesoanalysis. Quite a prolific number of occurrences (including today!) of STP over 10. That's pretty incredible.
stp.gif


Up next is the Significant Hail Parameter (again using SPC mesoanalysis formulation). (Note to self, increase the high end above 3.5 lol) But it looks like hail could definitely be in play during this event too.


ship.gif


Next is the Wind Gust Potential. This algorithm uses lapse rates and shear in the atmosphere to estimate wind gust potential on top of normal surface winds. While surface sustained winds rarely get above 40 mph, small cell-level gusts occasionally top 70 in the plot below.


Winds.gif


Up next is the Tornado Risk Index, which is scaled from 0 to 10 and hatched if Significant tornadoes are possible according to the model. The model gets up to 9 of 10 at times and throughout much of the forecast period, hatched Significant tornadoes are possible..

tor_risk.gif


The rainfall is also no joke! Some areas in Tennessee and Kentucky exceed 7 inches and 10+ inches locally.

rain.gif


I'll make another post in a bit with Composite Reflectivity + Threat Overlay and Profiles to do a deeper dive, but Wednesday - Friday certainly looks like an impactful event.
 
U can see the dryline west of KFDR, those cumulus bubbles are ahead of the dryline. I don’t expect those to be the ones. Give it another 30-60 minutes.
On his stream, Reed Timmer described the current towers as "they go up, they come back down".
 
Current situation. Interestingly enough, it seems the area the dryline is about to move into has negligible CIN and seems to be uncapped judging by the Skew T overlay.

View attachment 38241

View attachment 38242
Capping isn't too substantial where the dryline is right now but the T/Td spreads are quite significant. Still a fair amount of time until we have any storms with tornadic potential.
 
Capping isn't too substantial where the dryline is right now but the T/Td spreads are quite significant. Still a fair amount of time until we have any storms with tornadic potential.
Going off of what Trey said, before sundown would probably be the optimal time for storms to go. So we have around an hour to an hour and a half of that left.
 
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