Severe Weather for 4/19-4/23

[Moderately Unstable]

9 minutes ago, TexMexWx said:

There are new cells developing in SW LA, are those a concern wrt a continued tornado threat?

Well, mesoanalysis shows that the cells are in an environment with STPs estimated to be between 5-6 in about 2 hours, so, theoretically, yes. Overall instability is down from earlier today. As we go along through the evening, low level stabilization should result in storms becoming elevated, which would drop the tor threat. So, as long as they stay surfaced based, sure. But, medium term, they won't stay surface based I don't think. For now, yes. Anything in the area right now is going to spin. And for full disclosure purposes, as I've been writing this and looking at the models to respond, SPC has released a new MDD answering your question, basically saying, yeah, for now. That cell down in the SW is growing pretty fast. But again, as we go through the night, we see an increase in low-level stability. For storms to be tornadic, it isn't enough for there to be decent helicity. Storms have to have a wind field and inflow that actually uses it. Today has basically blown up at anyone trying to make a half decent forecast.

[Witness Protection Program]

 

5 minutes of drone footage:

https://www.click2houston.com/news/local/2020/04/23/aerials-drone-footage-from-onalaska-shows-the-trail-of-destruction-left-by-tornado-wednesday/?utm_source=twitter&utm_medium=social&utm_campaign=snd&utm_content=kprc2

[MUWX]

The storm near lake Charles certainly looks interesting 

[Buckeye05]

41 minutes ago, MUWX said:

The storm near lake Charles certainly looks interesting 

That one likely put down a tornado near Bunkie, LA.

[SouthernNJ]

Near JAN radar, looks curious:  1:53 AM Scan

 

[Buckeye05]

4 minutes ago, SouthernNJ said:

Near JAN radar, looks curious:  1:53 AM Scan

 

TDS there. Moving through the Jackson, MS suburbs.

[MattPetrulli]

Likely tornado approaching Thompson, Summit, and McComb, MS.

[MattPetrulli]

2 minutes ago, MattPetrulli said:

Likely tornado approaching Thompson, Summit, and McComb, MS.

TORR out with a TDS now

[cheese007]

Absolutely incredible video from Pecos Hank of the Madill tornado yesterday

[SluggerWx]

The Madill tornado continues to just mesmerize me - looking at damage today is pretty crazy. It looks like it just exploded in intensity within about 5-10 seconds.

[Witness Protection Program]

Dueling 'news' rooms:

(and check out that shadow)

That was in response to ABC13 in Houston running with the EF-2 claim for a few hours now.

[1900hurricane]

 

[Bob's Burgers]

You could probably justify a small enhanced risk tomorrow in the texarkana area tomorrow based off the 0z cams

[jojo762]

1 hour ago, Bob's Burgers said:

You could probably justify a small enhanced risk tomorrow in the texarkana area tomorrow based off the 0z cams

Was thinking the same thing. CAMs are in consensus that SE OK/ S AR/ NE TX will feature an area of enhanced severe potential, probably for all severe hazards.

Might make the drive down there to chase, looks like the last opportunity for at least a week... or two...? Terrain is very sub-par/god awful down there for chasing though; and looking at google maps, the road network looks pretty sub-par as well.

[yoda]

3 hours ago, Bob's Burgers said:

You could probably justify a small enhanced risk tomorrow in the texarkana area tomorrow based off the 0z cams

Actually pretty good sized ENH risk in that area... 10% TOR too

[Quincy]

Some shades of two days ago, obviously a bit different synoptically, but there will be a surface low moving east across Oklahoma with CI ahead of a dryline/cold front. Roughly 100 miles farther east. This time, CI seems more probable with southward extent, with more of a linear mode evolving north of the surface low into NE Oklahoma. 

The thing that jumps out to me the most are lapse rates. They look quite steep from SE Oklahoma into NE Texas. Storms may be more prolific hail producers than Wednesday was.

The tornado threat is most apparent near and south of the surface low.

[nrgjeff]

That's some tough chasing terrain near the Red River (both sides) 2-4 counties east of I-35. Boundary could lift into OK, but that's the tougher terrain.

Texas side offers higher dewpoint fuel and more ag clearings, though again not great. Trouble could be capping in TX but depends on surface heating.

Be mindful of Red River crossings. Cell motion might be to the ESE, vs the usual NE. Don't get trapped on the river!

If I still lived in DFW I'd be Paris bound this afternoon. Instead I just sit in Dixie and wait to get hit at night. Still salty from Easter.

[jojo762]

Looking like SFC d/Tds are going to be pretty sub-par across most or all of the ENH risk area... 

[cstrunk]

29 minutes ago, jojo762 said:

Looking like SFC d/Tds are going to be pretty sub-par across most or all of the ENH risk area... 

Yeah, not sure it will be enough to produce a big tornado threat. There's still a little bit of time for the low-60's dewpoints to head north. There are some readings around 60 in the Texarkana area, but plenty of other mid-upper-50's as well. The latest HRRR runs still show mid-60's to Longview this afternoon, but those don't make it any farther north. The cells south of the Red River don't look as robust as they did in earlier runs, either.

[Quincy]

Agreed with moisture concerns. Looks like mainly a severe hail threat initially. As the low-level jet strengthens and moisture return increases a bit closer to 00z, still think there is a bonafide tornado threat. Especially if the storm(s) near the triple point ride a pseudo warm front and don’t congeal into a messy blob. 

 

[cstrunk]

13 minutes ago, Quincy said:

Agreed with moisture concerns. Looks like mainly a severe hail threat initially. As the low-level jet strengthens and moisture return increases a bit closer to 00z, still think there is a bonafide tornado threat. Especially if the storm(s) near the triple point ride a pseudo warm front and don’t congeal into a messy blob. 

 

I agree the biggest threat will be right along the warm front near the Red River towards Texarkana. Storms south of there seem to struggle on the latest HRRR runs.

[Quincy]

Noting some weak convection near the Red River already. Likely elevated. Wonder if that ends up re-enforcing a moisture gradient down there. Could be just enough to stunt moisture return into SE OK a bit, but not totally sure. 

[Snowstorm920]

Latest run of the HRRRv4 has two areas of convection this afternoon. One in eastern OK and the other in E TX. The eastern TX storms look the most likely for tornadoes 

 

[cstrunk]

6 minutes ago, Snowstorm920 said:

Latest run of the HRRRv4 has two areas of convection this afternoon. One in eastern OK and the other in E TX. The eastern TX storms look the most likely for tornadoes 

 

The southern threat area from that model runs lines up with the deepening cumulus field east of DFW. Dewpoints are still struggling, with many locations stuck in the upper 50's.

[Quincy]

Based on latest trends from obs and high-res guidance, it looks like moisture return north of the Red River will be marginal at best. Forcing near the triple point should still result in vigorous convection, but I have some doubts about the tornado threat there. I agree that East Texas (especially north) looks better with respect to moisture and instability. 

I’m in Paris, TX and about to head south. Just came from Hugo, OK and it was overcast and gloomy there. I’m not a fan of the terrain southeast of I-30, so hopefully storms can initiate near or north of there. 

[Quincy]

Also: the low-level jet looks stronger in NE Texas as well. Confidence increasing that this will be the area to watch. 

[cstrunk]

I was wrong about what I thought was the cumulus field on satellite earlier.

There is an actual cumulus field deepening on the south side of DFW. I think initial storm development in TX may be just southeast of Dallas. SPC Mesoanalysis shows 2000+ SBCAPE, 200+ ESRH, 60+ knots effective bulk shear, and low 60's dewpoints in this area.

[Indystorm]

Storms now beginning to initiate se of Dallas metro

[Quincy]

Just now, Indystorm said:

Storms now beginning to initiate se of Dallas metro

Looks like they’re a little slow to get going, but the environment is becoming increasingly favorable. Low-level winds are backed to southeasterly downstream, although dews are still only in the upper 50s/lower 60s.

[janetjanet998]

URGENT - IMMEDIATE BROADCAST REQUESTED  
TORNADO WATCH NUMBER 146  
NWS STORM PREDICTION CENTER NORMAN OK  
450 PM CDT FRI APR 24 2020  
  
THE NWS STORM PREDICTION CENTER HAS ISSUED A  
  
* TORNADO WATCH FOR PORTIONS OF   
  SOUTHWEST ARKANSAS  
  NORTHWEST LOUISIANA  
  SOUTHEAST OKLAHOMA  
  NORTHEAST TEXAS  
  
* EFFECTIVE THIS FRIDAY AFTERNOON FROM 450 PM UNTIL MIDNIGHT CDT.  
  
* PRIMARY THREATS INCLUDE...  
  A FEW TORNADOES LIKELY WITH A COUPLE INTENSE TORNADOES POSSIBLE  
  WIDESPREAD LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 3  
    INCHES IN DIAMETER LIKELY  
  SCATTERED DAMAGING WINDS LIKELY WITH ISOLATED SIGNIFICANT GUSTS  
    TO 75 MPH POSSIBLE  
  
SUMMARY...SEVERAL SUPERCELLS ARE EXPECTED TO DEVELOP ACROSS  
NORTHEAST TEXAS AND SOUTHEAST OKLAHOMA, SPREADING EAST INTO PARTS OF  
SOUTHWEST ARKANSAS AND NORTHWEST LOUISIANA LATER THIS EVENING. A  
COUPLE OF THESE SUPERCELLS MAY BECOME LONG-TRACKED AND INTENSE,  
PARTICULARLY ACROSS NORTHEAST TEXAS.