2/24/07 FCST: OH/KY/TN/IA/KS/MO/TX/LA/OK/IL/AR

[Brandon Clement]

Well, it's descision time. According to NAM, GFS, SPC, and just about every other abbreviated source of info.....I'll be spending Friday around Tunica, MS... and then perhaps slide into Arkansas during the late morning. Dew points should be MORE than adequate, and that low-level shear!! Awesome. I'm afraid of the cloud cover somewhat, but with the intensity of this system, a lot can, and prob will happen that no one really expects, and that's what makes this one so interesting. I had thought of staying here (upstate of SC), and wait for Sunday, but other than a weakening squall line, I don't expect much here that day....so if anyone will be around Tunica - to SE of Little Rock Saturday, shoot me an e-mail!

Reminder to anyone that will be in the Ar/La/Ms delta tomorrow: The Ms river has very few places to cross. Memphis, Helena (Tunica), Greenville, Vicksburg and Natchez so be sure to plan accordingly.

As of now I will be in Lake Village, Ar. Lake Village has a few hotels with wifi, it is 8 miles from the Ms river crossing just south of Greenville, Ms and has road options in each direction and it is wonderful terrain. Of course this could shift 100 miles between now and tomorrow afternoon but the way the models have handled this system I doubt much change will be needed.

 

[Kevin Askew]

Caruthersville Mo. Is an excellent choice for a place to start. Access to TN or south to memphis. As it looks ATM. We are setting up Caruthersville, If anything changes, we will book either towards Memphis or Little rock areas. Either way we have a eastern & southern route. Plus I-55 corridor is very favorable chase territory, been to Blytheville many times.
Kevin

 

[Kevin Askew]

Forgot to say through this area, Good dew air & temps start becoming favorable for tornadic activity. I dont have to say a thing except WOW on the wind shear 500 & 850 winds. It speaks for itself lol

 

[Michael O'Keeffe]

I am leaving for Emporia tonight and spending the night there. I'm hopeful to maybe get some lightning photos/video from the squall that should move through the overnight and pre-dawn hours.

As for Saturday, I'm not exactly sure where we will target, but somewhere in the vicinty of Salina to Emporia. I find Emporia to be a good start for tomorrow. Moisture will be very meager only in the upper40s/low 50s, but the very strong shear profiles will overcome that and also produce CAPE to 750j/kg close to the surface low. The dryslot will clear out any of the left over convection and quickly destabilize the air for low-topped tornadic supercell development by the midday timeframe. Storms will be rocketing N to NE and will be producing mainly large hail and tornadoes. The strongest updrafts could contain some nasty hailstones even though instability will not be incredible, but suffient enough to sustain the updrafts.

So I'm hoping for a decent CC event to take place tomorrow across C/E KS eventually into W MO.

 

[Brian Stertz]

Ditto the head to Emporia-Marion KS idea...looks like development shortly after high noon..maybe even earlier. Cold core setup seems pretty straight forward on this event. Rich & Ryan Thies and myself will be heading down that way tomorrow morning. Hope to meet up with other chasers when we get camped out at or near my target zone. Looks like 52-55 temps may be sufficient for this CC event. By looks of the latest RUC, the main convective action shifts east by 9am and the back edge of precip is east of a Phillipsburg to Weliington KS line by 15z. Give it about 2 hrs past 15z, and things may fire before noon. Slight risk and 5% torn is about power for the course on CC events. The RUC is also showing a more aggressive trend with the 55 Td into S.Kansas...which could in turn make things a bit more interesting as the surface low deepens. At 15z (on latest RUC) the 985mb surfce low is located near Russell KS with a dryline down towards the west side of Wichita. There may be strong suggestion of a slightly further west CC breeding ground than previously expected. Hmmm...decisions...decisions.

 

[Bobby Prentice]

Eastcentral Kansas textbook "cold-core" tornado setup

The 00z/SAT NAM and SPC WRF 4-km forecast predict a textbook "cold-core" tornado setup over eastcentral Kansas between 18-22z. My pick is Osage County, KS at 20z (2 pm CST).

SPC 4km WRF Forecasts (00z runs only)

Those who chase this event will need to watch the real-time mesoscale data very closely to fine tune their target.

Tornadoes with Cold Core 500-mb Lows by Jon Davies - published in Weather and Forecasting, December 2006

Composite Digram (p. 10)

 

[SteveCarter]

El Dorado, AR. is my target area for 1500 Saturday. I'm in Greenwood, MS now. The tornado warning for Dodge City occurred with a 46 dew point, of course it was close to the low, but it just goes to show how dynamic and diverse this system truly is. I guess it's about time to switch to the NOW thread. Good luck all.

 

[Mike Peregrine]

Some crazy thunder here woke me up (for the first time in like 6 months) so I thought I might as well look through a few things.

By noon, RUC is placing 986-987 mb closed low smack in the middle of Kansas along I-70. I can't help but notice how RUC wants to draw the instability in really tight. Advection seems to be drawn nearly straight up into the system, with Theta-E ridge laying directly through the middle of Kansas that doesn't shift a lot until 18z, at which time this plume moves to the east considerably in response to swift dryline movement from the southwest and the eastward progression of the system. Looking at infrared satellite now, there appears to be a good area of clear air forming over SW Kansas following Friday's round. It looks to me like the cloud cover should eject from the region in more than enough time to reinforce instability (though not much in the way of reinforcement will even be required). In my mind, most of the criteria that we hear Jon Davies talk about are present for this to happen, and I believe we will likely see a few mini supercells during the afternoon in eastern Kansas.

After looking at this run, I think that personally, I would still target Dickinson/Marion county area by 1:00 p.m., and then be ready to move east toward Morris/Lyon/Osage county area along with the moisture as it moves. I'd try to be sitting under that Theta-E belt before the dry punch arrives. If you're positioned along I-70, you'll have the perfect east-west route lined up to move along with this storm. I agree with Bobby Prentice that realtime data is really important today. You won't need to be off by much to really get out of position, if you aren't paying attention.

 

[Mike Hollingshead]

I guess if I had to pick a target right now it would be a Concordia to Manhatten to Salina triangle.

Disclaimer: My targetting has been in the crapper for quite awhile now.

My 8pm target: Stuck in a ditch off I-29 south of Omaha.

18z streamline via 12z RUC

 

[Brian Thalken]

WRF - today's forecast with high-res nest

I wanted to share some WRF output from my run I initialized off the 00z GFS.

10km mother domain
3.33km nest over SPC moderate risk (15z-00z)

http://www.nebraskastorms.com/wrf.htm

Brian

 

[Bill Schintler]

Chase target for today, February 24

Note: this is for a secondary target in association with the upper-low and should result in an isolated and short-lived minor outbreak separate from the primary outbreak along the squall line several hundred miles to the south.

Chase target:
10 miles south of Lawrence, KS (30 mi SW of the Kansas City metro).

Timing:
Renewed storm initiation 3 PM CST.

Storm mode:
Isolated mini-supercells with a chance for short-lived tornadoes.

Discussion:
A narrow axis of instability will develop as heating takes place under an advancing clear slot while very cold mid- and upper-level temperatures spread in with the upper-low center (H5 temps of -25C). The orientation of the SFC and H5 lows is not conducive to optimal shear, however it appears as though a pocket of impressive shear (SFC-6km) to 60 kts and hodographs (SFC-3 km SRH of 200m2/s2) should coexist with SBCAPEs of 500J/kG.

[FONT=&quot]- bill[/FONT]