5/10/08 FCST: TX / OK / KS / AR / MO

[Brian McKibben]

SPC is going with a Slight Risk for Saturday May 10th, 2008.

The 00z 5/8 GFS shows a warm front extending across OK toward AR along the I-40 corridor. Td's of 60+ F can be expected within the warm sector. This will help aid in about 4000 j/kg of CAPE just E and NE of Dallas.

A nice h5 jet streak of 60kt is shown overspreading the area by 21z Sat. But convection may be suppressed along the dryline due to a strong cap. If strong heating occurs, I think we could break the cap and see some pretty decent supercells.

!!!Could a moderator please add LA/MS/TN to the thread title. Thank You!!!

 

[Karen Politte]

This is the thread that I came on to start...SPC have a SLGT risk out that contains a 30% probability - which is not too shabby for a potential chase day on the Day3 Otlk - on a Saturday.

Impressive moisture return forecast on Friday night/Saturday during the day for this next wave coming through on Saturday afternoon/evening. It is nice to see some real high-CAPE air promised now that we are in May. The differences between the main two models of the ETA and the GFS make it pretty impossible to forecast much for certain, with the ETA keeping most of the CAPE confined to northeast TX and the Red River vicinity. This doesn't seem to jive with other models, though - and the SPC expects there to be at least some tornado potential across the Arklatex/AR during the day Saturday. Given that it's May and therefore anything can happen - this one certainly bears watching.

KP

 

[Michael O'Keeffe]

After looking over the 12z and 18z WRF it looks like NC/NE TX could see some action on Saturday afternoon and evening along the dryline and warm front. Latest 18z WRF was showing this in NE Texas.
http://beta.wxcaster.com/models/meso-eta/central/CENTRAL_ETA212_ATMOS_CAPE_54HR.gif
If that is right get ready for some BIG hail. LOL. Also the 12z WRF was indicating dews between 75-78F over NE Texas. Overall with good upper level support, managable storm speeds, a decent low level jet, and good SRH along with the good moisture and CAPE. I think we may make the drive to NC/NE Texas on Saturday. Something else that intrigues me is that it doesn't show convection killing the setup like most east Texas setups. One of which we got screwed on back in March and some guys got screwed on last night. If the cap can break 90/75 air I think we are in buisness from the Red River down to I20, west from I35 over into the Arkalatex.

As of now I'd setup close to the dryline/warm front intersection somewhere near I10. Also the SigTor is at 7 by 18z Sat which could be mean an early show close to the warm front.

 

[Dustin Wilcox]

This is looking like a pretty sick setup for NE TX, SE OK and SW AR. Running through some forecast soundings reveals a pretty volatile atmosphere... anyone between me and the target area interested in chasing let me know....

De Queen AR at 21Z...
http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=045&STATIONID=KDEQ

That CAPE alone is worth chasing.... To bad Supercell Potential is only 100%
http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=048&STATIONID=KTXK

 

[Derek Weston]

Western Arkansas looking great according to the latest NAM. Slightly east of the largest CAPE, but they have the southerly 850s... Great directional sheer.

 

[Mikey Gribble]

The latest NAM looks awesome for tornadoes over SE Oklahoma and SW Arkansas, but it is quite a bit different from the 12Z run and the GFS, so I'm not getting excited about anything yet. If tomorrow's runs get on board with this I will be very excited though. I didn't look at the models very closely today, but one of the big differences with the 00Z (compared to 12Z) is that 850mb winds aren't veering. High CAPE, very good deep layer shear, and very good SRH over SE Oklahoma on the 00Z NAM would make for a great chase day if it verified (it would be an extremely favorable environment for tornadic supercells), but I have virtually zero confidence in that happening ATTM for several reasons. A few of those reasons are the models have sucked this year, the 00Z is quite a bit different from earlier runs of the NAM, and the 12Z GFS is a lot different (I haven't looked at the european yet). I will definitely be taking a close look at the models tomorrow though. It does give me some hope though. It would awesome to get a good chase in on Saturday.
Hey Dustin, I will be chasing with one or two other guys on Saturday if it looks good for tornadoes. You could meet up with us in ICT if you wanted to come along. Ryan Shirk usually drives my car and he has come close to killing us on about 35% of the chases so far this year, but aside from that we aren't too bad.

 

[Karen Politte]

I am eagerly awaiting the 12Zs coming out along with today's new D2 Otlk, but all in all Saturday is shaping up to be a more-than-likely chase day for us, living in central AR. After such success in AR a week ago, I should imagine that a few folks are probably looking at making the drive to LZK's CWA tomorrow...

SPC's first D2 went with a MOD and a 45% hatched probability area across almost all of AR except extreme northern AR, and also into NE TX, NRN LA, and NRN MS.

What is encouraging about tomorrow's scenario is that there is forecasted to be a significant - but eventually breakable - cap in place across much of the outlook area during the first part of the day. It is fairly unusual to have a potential AR chase day begin with the potential for no convective junk or racing CAPE-eater squall line working over the area at 8AM. I am quite excited about the possibility of getting a true supercell chase day in AR for the first time since April 2nd, 2006 (that's the first time since I saw one - not the first time since it happened! ). It would be so nice to just be out there and have blue skies and explosive convective development - let along tornadoes. I can't really remember what hard-looking convection looks like!

Anyway - like I said - eagerly awaiting the 12Zs......but primary target for tomorrow is central-eastern AR along the warm front. Will be hoping to avoid the dryline and CAPE-ola in NE TX like the plague, don't particularly think Mena, AR is a very good target area.

KP

 

[Derek Weston]

Kind of surprised by the SPC's wording on this one.... "a few tornadoes" Not exactly sure why they only say "a few" -- seems there could be a good deal more than that potentially.

To me, this looks like a potentially strong tornado setup. Over Arkansas specifically. Very basically: we're going to have enough moisture, we're going to have the directional shear. I guess the strength of 850s spooks me a bit... winds at lower levels are quite a bit strong. Not sure how much of a cause for concern this is...

 

[Verne Carlson]

Definitely looks potent in the areas and I am happy to see northern Texas a bigger play and 4500 CAPE to play with. Going to be a bit of a haul for us heading out, but it looks like we could have a fair shot of supercells before racing into the trees.

It would be so nice to just be out there and have blue skies and explosive convective development - let along tornadoes.

Oh, by the way, Karen, that's NOT how you spell alone...

 

[Dustin Wilcox]

I still like the corridor between DE Queen and Arkadelphia by the 0Z time frame

http://beta.wxcaster.com/cgi-bin/parse_skewt_trace.cgi?model=NAM&fcsthr=021&STATIONID=KDEQ

Wouldn't rule out something a little further North as well, looks like it could be a pretty early show especially the further North you get with CAP all but gone by about 20Z, I think I would still hold tight in the De Queen area... I'm almost tempted to get in the car right now and start heading down, though It'd cost about $125 in gas Just to get there, throw in motel costs ext.. think I may be content to sit it out, though not an easy choice.

 

[Bill Hark]

There will be a very impressive set-up for today across extreme eastern OK and Texas, Arkansas and Louisiana but I have some concerns. I like the strong 50-60 winds at the 500 level from the west as shown on the NAM though the GFS gives a more northwesterly prog. The cap may limit convection farther south into east central Texas but shouldn’t be much of a problem in OK. (using 700 mb temps) There will be a narrow area of very high CAPE to 4000 J kg extending into southeastern Oklahoma, very high lifted indices, and very high storm relative helicity centered over Arkansas. The surface low is progged to shift rapidly northeastward across northern Oklahoma eventually to northwestern MO by 00Z Sunday on both the GFS and NAM. This will result in nicely backed winds but they will too quickly veer for the forecast area. I really don’t like the veered 850 winds for the entire area. Currently, I would target Broken Bow, Oklahoma and wait for AM data. The road network in that area is awful.

Bill Hark

 

[Brian Emfinger]

Well I have never seen a Mesoscale Discussion that only highlights the anticipated upgrade and refinement of a convective outlook (thats 4 hours away!). They are expanding the mod risk area into S. ILL/SEMO/SWKY/TN/GA as well as keeping its current placement. This would have to be one of the larger mod risk areas I have ever seen. Still tough currently to figure out where exactly to target as that all depends on things that aren't still nailed 100% down. Luckily I can stay at home much of the day and go over everything in comfort.

 

[Doug Mitchell]

Sleeper day in E KS if latest RUC runs verify. ~1500 cape and decent shear showing up. RUC is probably be too optimistic on moisture return though. Obs current in TOP are 51/48 and RUC says 60 dews will creep up to the I-70 corridor by 21z. If things go according to plan, I'll probably stick close to home, maybe drift south towards Ottawa and Garnett, KS.

UPDATE: 12z run goes crazy on moisture. Either way, I still think the big negative for KS is that the cold front will be sweeping through and could undercut everything.

 

[Matthew Fischer]

where to stop and wait???

As of right now, are current target is northeast AR. Depending on where the warm front is set up. Warm front looks to be the best play for the time being unless we need to shoot south toward srn ar. We (Adam Lucio and I) don't want to head west into the Ozarks. So we are going to sit in the MS valley and see what happen.

 

[Jeff Piotrowski]

Target area today KS/OK/MO/AR

Tornado outbreak today based on Ruc now 65 DP all the way to MCI a head of surface low. Tornadic storms will form by 21Z from EMP, FSM, LIT lifting ENE along warm front. Damaging tornado's are likely from EC OK/ AR along the I-40 corridor. The warm front goes nuts today!!!!