5/7/08 NOW: OK/TX/AR/LA

[Brian McKibben]

A tornado watch has been issued for N. Central TX and S. Central OK.

There are a couple of storms that just fired up along the Red River near the triple point just east of SPS.
http://www.srh.weather.gov/oun/enhancedwx/fxc_Regional_Weather.jpg?timestamp=1210186400

dbZ already up to 60. There is plenty of moisture in the area, Td's > 60 F, and the shear is increasing just to the east of the storms with at 55-60kt LLJ.

There is also clearing along the dryline down toward central TX.

Things are starting to get interesting.

 

[Brian McKibben]

Storm in Stephens and Jefferson Co. Oklahoma is now severe warned.

* AT 224 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
SEVERE THUNDERSTORMS ALONG A LINE EXTENDING FROM 5 MILES NORTHEAST
OF ADDINGTON TO 4 MILES WEST OF SUGDEN...MOVING NORTHEAST AT 39
MPH. HAIL UP TO THE SIZE OF QUARTERS AND WINDS OF 65 MPH ARE
LIKELY.

 

[Willoughby Owen]

Heading eastbound through Wichita Falls right now and the turkey towers in view are just absolutely getting ripped apart by the strong mid-level shear. Shall wait and see...

 

[Mikey Gribble]

I just copied and pasted this from my blog. I haven't had any time to forecast today until about 30 minutes ago, so I just glanced this over. Best of luck to anybody chasing. I wish I was down there. Anyways, here is the post I made on my blog...

I would be sitting in Plano, Texas right now, which is just on the east side of Dallas. I think any discrete storm that comes along or 50 miles or so South of this area will start to have decent tornado potential after it gets NE of Plano area, with tornado potential increasing as the storm moves towards the Red River (tornado potential should peak near the Paris to Red River and just North of there with these storms).
As cloud cover breaks ahead of developing convection along the dryline there should be a couple hours of insolation to enhance instability. You are getting better clearing (ahead of the dryline) south of the Red River, but surface winds start to back harder North of the Red River enhancing lowlevel shear. I think any storm that fires between Forth Worth and Waco and tracks up towards the Paris area will have the best tornado potential over the next 5 hours or so. This area will have a good compromise of those two qualities (backing winds and clearing/insolation ahead of developing convection). If it wasn't for modest instability I think there would be some really good tornadoes today. The tornado potential is going to be directly proportional to how much insolation and instability can develop ahead of the developing convection along the dryline, since everything else seems to be pretty supportive of tornadic supercells. Extrapolating satellite/radar loops makes me think there will be about a 2 hour window of insolation ahead of these storms, allowing a subtle increase in CAPE. I haven't spent much time on this so take it with a grain of salt. I will post my long range forecast in a few hours.

 

[Brian McKibben]

Tornado reported in HASKELL and THROCKMORTON county in TX. This storm is basically right under the upper level low.


* AT 256 PM CDT...LOCAL LAW ENFORCEMENT REPORTED A TORNADO 2 MILES
NORTHWEST OF WEINERT...OR ABOUT 14 MILES NORTH OF HASKELL...MOVING
EAST AT 30 MPH.

 

[Alex Lamers]

That cell on the Red River will have some potential in the next half hour. 75/68-ish now in Eastern Jefferson and Western Love Counties. Nice strong low level flow as well...and perhaps an outflow boundary to work with.

AJL

 

[Willoughby Owen]

Confirmed rotation on a developing storm just east of Henrietta TX

 

[Alex Lamers]

A couple of cells of interest. Still liking the one on the Red River the best. Appears to be moving right of the mean storm motion and a bit slower too. Waiting on a few more scans of trends before I would call it a right mover. Very interesting prospects for that cell though. Moving into an area of 200-300 m2/s2 0-1km SRH.

Also...Comanche County OK. 2.75" mx hail on cell attributes off KFDR. Not too shabby. Right under the upper level cold pool.

AJL

 

[Dann Cianca]

Tornado in Casper, Wyoming right now! Storm is also putting down 1.5" hail.

 

[Dann Cianca]

Tornado in Casper, Wyoming right now! Storm is also putting down 1.5" hail.

NWS had reworded the warning:

AT 311 PM MDT...COUNTY EMERGENCY MANAGEMENT REPORTED A VERY LARGE
FUNNEL CLOUD. THIS POTENTIAL TORNADO WAS LOCATED JUST SOUTH
EASTRIDGE MALL...

Beforehand, EM had reported a tornado. Close enough anyway ... time to get in the basement if you're in Casper.

 

[Alex Lamers]

Interesting observation from Sheppard Air Force base.

KSPS 072131Z 27034G47KT 5SM -TSRA SQ SCT037 SCT200 18/12 A2957 RMK AO2 PK WND 26047/2127 TSE02B31RAB31 PRESRR P0000

Not a shabby gust! These things appear to be doing a decent job producing some strong wind gusts. It's probably those steep mid level lapse rates. Major hail producer there in Love County still. Got a golfball report over the spotternetwork.

AJL

 

[Brian McKibben]

I don't see the tornadic threat panning out for this event. I think the low is too stacked (as per spc mesoanalysis and oun 18z sounding) and therefore we are seeing too much unidirectional shear. The speed shear is great but then again we don't have much in the way of instability. I imagine discrete supercells will continue to develop but the tornado threat in TX/OK doesn't look optimal right now.

For the hope of chasers our there, pray that I'm wrong. (as long as the naders stay away from life and property)

 

[Chris Vagasky]

Tornado reported on the ground by Oklahoma City Police near Wiley Post Airport

 

[Mikey Gribble]

I like the storm straight North of Plano about 30 miles (approaching highway 75). I feel kind of stupid saying that because it's been going a while and hasn't even prompted a severe warning yet (not sure what has been holding it back), but it is discrete, clouds have cleared and they are getting insolation North of the Red River (downstream from this storm), and it should continue moving into increasingly favorable lowlevel shear. I agree that the tornado potential isn't that good. I'm not on board with the "strong tornado" threat, but there is a lot of day left and I wouldn't be surprised to see a tornado along and either side of the Red River in SE Oklahoma-NE Texas. The killers for the tornado potential is the veering 850 (although I think this is offset a tad by strong speed) and the mediocre CAPE. My biggest problem though is the veering 850 and as mentioned before the stacked system which is causing very little turning in the 850-500 overlay. When you have strong speed shear though you can always get a weak tornado or two IMO, so I don't think the tornado threat is zero.
edit - I guess I don't feel stupid any more since it just went tornado warned.

 

[Alex Lamers]

Speaking of interesting observations, here's the latest observation from KPWA (Wiley Post in OKC)...

KPWA 072212Z 28027G50KT +FC TSRA 17/14 A2948 RMK TORNADO B11 3SM E MOV E AO2 PK WND 31050/2210 LTG DSNT ALQDS TSB06RAB10SNB08E10 P0004 $

wow! who'd have imagined that.

AJL