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3/10/10 FCST: KS,MO,OK,TX,AR,LA

Vort over LBB attm will swing out neg. tilted across E. OK/AR/SW MO creating an active supercell and tornado day later this afternoon/night. Quick scan of data and other info puts my initial afternoon hard target at Chelsea OK and then points north and northeast along the I-44 corridor. Too bad things have shifted that far east into the less favorable chase area...but it is still early March and climatology certainly favors this sort of severe wx event...with the position of the LL/UL features. Looks to me to be a MDT risk scenario. Action will happen fast n' furious when things do gel and explode this afternoon....
 
after doing some hand analysis you can see an area of temps in the upper 60's/low 70's already in northeast OK/northwest AR/southwest MO with the sfc low back along the TX/OK and DL pushing east with storms along it down in TX

really nice clearing where the warmer temps are and along the I-44 corridor in MO. should see storms go up pretty quickly this afternoon and move north and east pretty fast. wouldn't be suprised to see SPC go MDT later on

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I'm out of this setup, working all day. Hopefully being "out" keeps my forecast free of personal bias.

I think y'all got a good shot in eastern OK. I know that runs up into the Ozarks, but I'd give it a shot. See if things can gen up pre-Zarks. Nice low level backing in progress; and, somewhat up to 850. Moisture is not there as I write, but agree with Mike and Jordan that it will be there. S/W assuming a slight neg tilt which might be just the extra kick you need.

Central TX is another possibility with excellent jet energy and great sfc moisture. The 850 winds are not as backed in the Lone Star State, but this is early season March Madness. I will try to add value to the Nowcast later today, but it will be from work.

Happy and safe chasing!
 
My 16z hand analysis indicates a small boundary positioned across Tulsa dividing the NE portion of OK stretching into southern MO. I don't think SPC's mesoanalysis is picking up the boundary or position of the lows very well. I'd check the Mesonet for a more accurate depiction of the surface setup.

There's gonna need to be some more moisture advection from the south to light up NE OK. LCL heights don't look that appealing as of this moment. If that happens, I would focus on that boundary.
 
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SPC says at 1630Z, "MOISTURE RETURN APPEARS TO BE THE PRIMARY LIMITATION ON UPGRADING TO A GREATER RISK FOR TODAY." Today is going to be a test on my theory that the ground is so wet that we don't need the traditional "wide open Gulf" in order to get early-season severe weather outbreaks. I suspect we will see enough reports to have justified "moderate" risk by the end of the outlook period.

That's a good point. Monday's event was aided by the above normal soil moisture in place across most of Texas, which I think kept the quality moisture from mixing out like what normally happens during early season severe events when the Gulf moisture is 'questionable".

Today a similar scenario is true. The tongue of rich low level moisture advecting into eastern Oklahoma is not being mixed out as it advects north across central/eastern TX nearly as much as it could if the ground was bone dry. Thus, deeper moisture may indeed be able to rap around the surface low and feed the cold core supercells that form later today over northern OK/southern KS, enhancing the tornado threat.
 
Just briefly looking at the obs and profiler data, it looks like this could be a big night for damaging wind and isolated tornadoes. There is a deep boundary layer in place across S. AR and a nice jet streak entering the region. I wouldn't be surprised if this turned out to be a sig wind event (LEWPS) in AR/MO tonight with a few isolated long tracked tornadoes. Definitely looks like a moderate risk event to me IMO.

Best of luck to everyone going out.

BEST GUESS TARGET: MOUNTAIN HOME, AR.
BEST GUESS TIME: 03z.

Eddie
 
Mesonet analysis of ThetaE, Tds, Winds...Lows in SW OK, NE OK, Dry Line in SW OK, Secondary moisture boundary extending from E Tulsa to the Red River...
 

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I personally don't see any reason to upgrade to a moderate risk. I was planning on chasing today, but decided not to a couple hours ago. I just don't see anything that is terribly impressive.

There is an arcing line of crapvection rolling through the target area as we speak. This in addition to fact that the WRF high definition run from last night has not been accurate with precipitation so far took away most of my confidence in the idea that you would get some good discrete storms over the northeast quadrant of Oklahoma.

I think the moisture situation will be fine over eastern Oklahoma, especially south of I40 where you already have mid 50 dewpoints. Farther north over northeast Oklahoma I think moisture might be more of a problem, especially in the wrap around area northeast of the surface low.

Another concern I have is LCL heights. They are obviously better down in the southeast portion of the state where ttd spreads are a little better, but they are still higher than I'd want to see them. North of I40 LCL's are a pretty serious problem IMO. They should improve through the afternoon, but I still think they'll continue to be an issue.

The RUC has been hinting at some convection trying to fire up ahead of the arcing crap in northeast Oklahoma, but who knows if that will verify. The models have left a lot to be desired with handling precipitation today. I think that is about your only chance for a low end tornado threat over the northern portion of the risk area.

I think there is a slightly higher tornado threat down in the southeast portion of the state where LCL's are lower and you have some decent instability, but I'd still say there is only an outside risk of tornadoes during daylight hours.

It's a tough forecast and I could very easily be wrong so don't let me discourage you if you're chasing. The shear is pretty good. I really like that you have decent 850/500 crossover. I thought that might be a problem a couple days ago. 0-1km SRH is respectable and should improve through the afternoon, so there definitely are a few positives.
When you look at the whole picture though I just don't like this setup much. There definitely is a chance for a couple tornadoes, but if it happens I think they'll be weak and more than likely not very chaser friendly (terrain and daylight issues). You never know though. Storms do some unexpected things with closed lows like this. They're definitely not my favorite to forecast.
 
Robin T., Dan D., Gabe G., Jana H., I, and a few others are sitting in western Tulsa, trying to assess what to do. The best t/td combo is in far eastern OK and adjacent parts of AR. However, that is really difficult chase area, so we're not committing that anything in the current "crapvection" band across eastern Oklahoma (which is, incidentally, transporting down western momentum and a little drier air from aloft it looks). Our current idea is to turn to the west and focus on the sfc low. The effects of the mid-level cooling are evident on vis and TLX/FDR radar as Cu and showers develop in southwestern Oklahoma in drier air behind the dryline. Behind the eastern "crapvection" band, winds have returned to the southeast, and the 50F isodroso isn't too far from I44 southwest of TUL. We are hoping that this higher moisture can advect closer to the warm / stationary front as the mid-level cold pocket continues to press eastward towards central and eastern Oklahoma. We are seeing the convection developing N of OKC, and this may become the "play" a little later as continued insolation helps steepen the low-level lapse rates and the mid-level CAA steepens the mid-level lapse rates.
 
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