2011-04-26 FCST: TX,OK,AR,LA,TN,AL,GA

[Jeff Piotrowski]

After looking at all of the 0Z model data including 4KM, HRRR high Res data.

The mid 60 DP will rapidly return N/NW into NC/NE TX SE/OK and Southern AR during the day.

The surface low in TX PHNDL deepens moves toward NC/TX by around 6Z.

With 2000- 4000 capes along with 200-600 3KM helicity a Waco/DFW/SPS eastward toward Little Rock south into northern LA.

I expect tornadoic storms to explode over parts of NC/NE TX and SE/OK around 0Z-3Z time frame and track ENE toward the TXK area.

The storms will produce long tracked tornado across NE-TX SE/OK and Southern AR overnight.

I would think Moderate risk will come back to the I-35 corridor based on the new data.

10:14 am update: HRRR & RUC explodes storms NE & S/SE sides of DALLAS by 21Z.

 

[Brandon Clement]

I was wondering when this thread would get started.

There seems like an extremely good chance of a long track violent tornado tomorrow evening, particularly in SW Ar. The area just to the East of TXK around the Stamps, Ar area. At 00z there will be 2500 j/kg, 250-300 0-1 rapidly increasing to >400, LI of -9, the winds back nicely out the SE, 60 knots of bulk shear. The SREF is painting a sig tornado of 8 all along this area. The HRRR breaks out sups in E. Tx and OK earlier but also fires some stuff in the TKX area. The WRF paints a couple fat sups along this area and has them as right movers and tracking all the way into central Ms. There also seems to be some sort of outflow boundary draped just south of the I-30 corridor from last night's convection that should enhance already stout helicity and provide a nice focal point for some innitiation.

Cloud cover should not be an issue, particularly for the Southern half of the moderate risk. The cap looks great, holding off convection until prime heating. Bulk shear is great and should help to keep storm mode cellular. I was somewhat surprised to see SPC hold off on the high risk. The only concern I have is the cap breaking too early before the low level shear is in place allowing storm mode to go linear before all the ingredients come together.

Idabell to Hugo also looks great, just afraid forcing is going to be a bit much in this area.

 

[jeremy wilson]

Not sure why nobody here is talking about it...this board is dead.

Because dude, nobody wants everybody to know their target area!! ( C'Mon fellow geeks, admit it)

Heres mine, Greenville, TX up to Paris TX. Love the shear and instability combination tomorrow just south of the river. With OFB's in place and other factors that have not yet been pinned down I think anywhere around the Greenville area would be a good bet for nasty cells to get maturing.

Won't be surprised if the risk doesn't ease west a bit tomorrow afternoon. The Metroplex may not be out of the woods yet...

 

[Trey Thee]

SPC went high risk. I expected that, but not until noon. I have not had a chance to analyze the models this morning in great detail but my initial reaction is they nailed down the high risk area pretty well, with perhaps a bit of a shift to the east depending on what the shear environment looks like mid evening. Given the amount of upstream rain we've seen the last few days, I urge anyone who's chasing to be very careful, do not put yourself in a situation where you are getting chased down roads you are unfamiliar with. You may find roads flooded or partially washed out and impassible.

The instability and shear combinition looks to be very impressive within most of the MDT area and even more so within the now high risk area. I suspect we'll see a PDS around noon or 1pm and start to see things fire up between 3pm and 5pm. At that point storms will go severe quit quickly and the tornadic threat will be highest from 5pm through about 9pm.

 

[weskranz]

I think we'll see a couple early cells between Lone Oak and Commerce. I hope to depart around 1:00pm for an initial target of Cumby, TX. Clear skies here in the DFW area will help build temps as the warm front approaches with strong southerlies. Stay safe today and good luck to all chasing.

 

[Michael Riedl]

Upper air dynamics for today and especially for Tomorrow look off the charts.

For today, unlike yesterday clearing is underway, and supercells should be the dominant mode for a good 2 Hours IMO. CAPE will be abundant, and effective SRH (around 400-500 m^2/s^2) will be about the same as yesterday. All signs pointing to long track tornadoes across Southern AR and NW Texas.

 

[Brian Mette]

Every parameter looks amazing for today! This may too good of a setup for me to pass up on, despite it being a school day. If I do decide to go, I'll probably head down to Paris, TX as my initial target, and adjust further south from there. I am really liking the EHI (0-1 KM) and helicity values for northeastern TX.

 

[Chip Redmond]

I don't really think that linear storm mode will be that big of an issue from to much forcing. The models seem to agree with surface winds from Dallas into central Arkansas seem to continue out of the south well through the night and into the early morning. HRRR is spitting out supercells around the Dallas area at 22-23z. The only problem I see is when the cap goes there is going to be so much instability that it could congeal into a MCS. As the LLJ amps up after dark but it could be to late for the supercellular convection to make the most of it and just feeding a very potent cluster/system of storms through AR.

Chip

 

[Trey Thee]

Definitely looks like they will be expanding the high risk to the east as I anticipated. Dynamics continue to look very impressive and have improved just a bit over the eastern half of the MDT.

Chip, I was also thinking we could see a situation where everything goes up and they choke off inflow to individual cells and the result is a large mcs or large area of heavy thunderstorms. This could still be a potential issue, however, the upper air seems to indicate embedded tornadoes would be likely if that scenario did happen. This is making the setup all the more dangerous as embedded tor's are hard to spot visiually and can potentially cause some radar issues as well.

 

[Mark Meyers]

Edit

Warm front never made it into the DFW area...cool north wind as of 836pm....
Edit

 

[Drew.Gardonia]

starting to see some diurnal heating here in Middle TN as the cloud cover has become very high based, and surface temps are beginning to rise, it was low 60's this morning when I went to class, surface temps are now hovering near 70 and beginning to climb. Water Vapor satellite on COD radar shows some partial clearing to the west of Nashville, back into Arkansas, the atmosphere should become relatively unstable over the next few hours, with the increased surface heating and moisture from this morning's round of storms. timing of storm initiation in TN is uncertain, but the GFS seems to indicate around 03Z - 08Z (10pm - 3 am CDT) for, but that could vary depending on several factors.

edit: sorry for the confusion, im still struggling with this cursed Zulu time conversion....far as I'm concerned they can stick that where the sun don't shine.