Severe Weather Threat May 7-10, 2024

[CheeselandSkies]

Meanwhile, 0Z HRRR looks nasty for Wednesday over east-central to SE MO, southern IL, and parts of TN/KY. 0Z 3KM NAM suggests things could get a little frisky around here for me tomorrow afternoon. Parameter space isn't huge but sufficient given high 3CAPE values and steep lapse rates shown on the forecast soundings. HRRR is less enthusiastic but still has little popcorn cells on the simulated reflectivity.

 

[JBishopwx]

Tuesday

 

[TornadoFan]

Tuesday
View attachment 26666

Boy, they really expanded that.

 

[cincywx]

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1210 AM CDT TUE MAY 07 2024

VALID 071200Z - 081200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE OHIO
VALLEY...

..SUMMARY

SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED ACROSS THE OHIO VALLEY
TODAY. A FEW TORNADOES, POTENTIALLY STRONG, LARGE TO VERY LARGE
HAIL, AND SEVERE/DAMAGING WINDS ALL APPEAR POSSIBLE.

..OHIO VALLEY

PLAINS UPPER TROUGH WILL EJECT NORTHEAST ACROSS THE MID/UPPER MS
VALLEY EARLY IN THE PERIOD AS 80+KT 500MB SPEED MAX TRANSLATES FROM
NORTHERN OK INTO WESTERN IL BY 18Z, THEN INTO EXTREME SOUTHWEST MI
BY EARLY EVENING. PRIMARY CORRIDOR OF MID-LEVEL HEIGHT FALLS WILL
SPREAD NORTH OF THIS JET, THOUGH 30-60M, 12HR FALLS ARE EXPECTED AS
FAR SOUTH AS I-70 ACROSS IN/OH DURING THE EXPECTED CONVECTIVE CYCLE.
IN RESPONSE TO THIS SHORT WAVE, SOUTHWESTERLY LLJ WILL SHIFT INTO
IL/IN BY 18Z, THEN INTO THE MID OH VALLEY BY LATE AFTERNOON. THIS
EVOLUTION WILL ENCOURAGE CONSIDERABLE MOISTENING EARLY IN THE PERIOD
AND BUOYANCY WILL INCREASE MARKEDLY BY MID DAY WITHIN A STRONGLY
SHEARED, BUT DEEP SOUTHWESTERLY FLOW REGIME.

CURRENT THINKING IS ONGOING CONVECTION, ASSOCIATED WITH THIS TROUGH,
WILL PROPAGATE INTO THE MID MS VALLEY BY DAYBREAK, THEN ADVANCE
DOWNSTREAM WITH SOME PROPENSITY FOR WEAKENING DURING THE MORNING.
HOWEVER, BOUNDARY-LAYER HEATING AFTER THIS INITIAL ACTIVITY WILL
RESULT IN A MODEST-STRONGLY UNSTABLE AIR MASS BY EARLY AFTERNOON.
CONVECTIVE TEMPERATURES WILL BE EASILY BREACHED AS READINGS WARM
THROUGH THE 70S TO NEAR 80F, AND ISOLATED-SCATTERED THUNDERSTORMS
SHOULD EVOLVE ALONG THE SOUTHERN FRINGE OF THE MAIN JET CORE.
FORECAST SOUNDINGS ACROSS THE OH VALLEY EXHIBIT FAVORABLE
SHEAR/BUOYANCY FOR SUPERCELLS, ESPECIALLY GIVEN THE STEEP LAPSE
RATES. STORMS THAT EVOLVE WITHIN THIS ENVIRONMENT WILL LIKELY REMAIN
DISCRETE, OR PERHAPS EVOLVE INTO SOME CLUSTERS. TORNADOES, A FEW
STRONG, ARE POSSIBLE ALONG WITH VERY LARGE HAIL. SOME DAMAGING WINDS
ARE ALSO POSSIBLE.

..TX

WHILE THE PRIMARY UPPER TROUGH WILL HAVE EJECTED WELL NORTHEAST OF
THE SOUTHERN PLAINS BY AFTERNOON, TRAILING SURFACE BOUNDARY ACROSS
TX MAY PROVIDE ADEQUATE CONVERGENCE FOR A FEW STORMS LATER TODAY.
STRONG SURFACE HEATING IS FORECAST ACROSS WESTERN INTO SOUTH-CENTRAL
TX. WITH READINGS EXPECTED TO APPROACH 90F NEAR THIS BOUNDARY,
CONVECTIVE TEMPERATURES MAY BE BREACHED ALLOWING ISOLATED
THUNDERSTORMS TO EVOLVE WITHIN A STRONGLY SHEARED ENVIRONMENT. IF
SO, A FEW SUPERCELLS COULD EVOLVE AND LARGE HAIL WOULD BE THE
PRIMARY CONCERN.

..DARROW/WENDT.. 05/07/2024

 

[TornadoFan17]

10% hatched in the ENH area.

 

[buckeye05]

Dayton and Columbus metros under the gun again. Just great…

 

[Fred Gossage]

Meanwhile, 0Z HRRR looks nasty for Wednesday over east-central to SE MO, southern IL, and parts of TN/KY. 0Z 3KM NAM suggests things could get a little frisky around here for me tomorrow afternoon. Parameter space isn't huge but sufficient given high 3CAPE values and steep lapse rates shown on the forecast soundings. HRRR is less enthusiastic but still has little popcorn cells on the simulated reflectivity.

And then the beginnings of the nocturnal sigtor threat for Wednesday night there at the end of the 0z HRRR run back in central Arkansas... with a 40-45 kt low-level jet ramping up over in my area by sunset. Interested to see how this evolves going forward as we get the overnight/predawn period on into the HRRR range.

 

[Kds86z]

10% hatched in the ENH area.

Oh geez.probably will outperform today lol

 

[Telstar]

To Clancy: I notice that you post radar images in a four-block format. It looks a lot like the new radar app that I have just discovered, called wX. Is that what you are using? If so, I’d love to know which four radar images you use. I use the velocity and cc but I’m not sure which other two choices are best to use.

To Casaurena Head: I’m interested in your opinion of Wednesday’s threat to middle Tennessee. Do you think we will get tornadoes? Thanks!

 

[tennessee storm chaser]

To Clancy: I notice that you post radar images in a four-block format. It looks a lot like the new radar app that I have just discovered, called wX. Is that what you are using? If so, I’d love to know which four radar images you use. I use the velocity and cc but I’m not sure which other two choices are best to use.

To Casaurena Head: I’m interested in your opinion of Wednesday’s threat to middle Tennessee. Do you think we will get tornadoes? Thanks!

Yes being night threat the , lower level jet will increase over night to enhance the tornado risk … think spc has good handle on the northern part Tennessee getting tornado

 

[Tanner]

09z HRRR was a run that happened.

 

[TornadoFan17]

For the next D2 update, is there any chance that we'll see the SPC expand the ENH further south? Or are models pretty much in consensus that the main threat is for Missouri and the upper Ohio River Valley?

 

[buckeye05]

High confidence in numerous discrete supercells across the Ohio Valley today. Also, pretty much every forecast office in the 10% hatched area explicitly mentions a strong tornado threat this afternoon and evening, the CAMs paint the region with UH streaks, and soundings look favorable (or as ILN calls it, "concerning", a word I learned to dread when I would see it in their discussion when I lived there). This might sneak up on us and be uglier than many are expecting, especially in the shadow of a High Risk day. I've let all my friends and family back home to be vigilant today, especially with my mom's retirement ceremony taking place in Dayton this evening.

 

[buckeye05]

Beavercreek, OH area early this evening. HRRR has discrete cells in this environment

 

[cincywx]

69/64 here in cincy already. Remnants of last night's QLCS in OK will be here midday, but if they slow down at any point, it's going to be tough for much to get going across SW OH later in the day. Interested to see how this unfolds because the ~12z-14z HRRR yesterday actually depicted what ended up occurring last night in OK.

 

[Clancy]

To Clancy: I notice that you post radar images in a four-block format. It looks a lot like the new radar app that I have just discovered, called wX. Is that what you are using? If so, I’d love to know which four radar images you use. I use the velocity and cc but I’m not sure which other two choices are best to use.

To Casaurena Head: I’m interested in your opinion of Wednesday’s threat to middle Tennessee. Do you think we will get tornadoes? Thanks!

For the most part I use GR2A for radar imagery, and typically have differential reflectivity or NROT in addition to the reflectivity, velocity and CC panels.

 

[cincywx]

 

[buckeye05]

This is disconcerting in combination with ILN being pretty bullish with the strong tornado threat in their latest discussion. Also saying the sigtor risk may be particularly elevated along a corridor extending from Cincy to Dayton. Stay safe out there today.

 

[Telstar]

For the most part I use GR2A for radar imagery, and typically have differential reflectivity or NROT in addition to the reflectivity, velocity and CC panels.

Ok. I think those are the ones I’m using as well. Thanks! I was pleasantly surprised last night to spot some rotation in Tennesse that was affirmed by someone else on this board. It makes me feel safer knowing I might be able to spot trouble in a local area by myself.

 

[atrainguy]