Chase Day 23 Discussion - MODERATE risk OK, KS, AR, MO, IL

[nsrobins]

What a start to Tour 4. Another potentially dangerous situation for central and east OK, NW AR, SE KS and into IL this afternoon and evening.
Very rich moisture offers CAPE in excess of 5000 from the OKC to NE OK into the AR/OK/KS/IL corners region. The big player is a surface trough expected to extend into S KS providing backing at the surface. There is up to a 70kt wind from the WSW at 500mb. The sounding for Tulsa at 20Z provides the sort of horizontally elongated looped hodo that raises eyebrows. Complex set-up as per usual and caveats apply but once again the potential for strong long-tracked tors exists in the moderate risk area.

[robt]

Looking at the predictions, the dry line is on a similar sort of alignment to yesterday, and the risk area is the broad area from Lawton in the SW up towards Tulsa and Joplin in the NE. 

 

There is talk of possible long tracked cells forming, and looking at yesterdays events with the cell the guys dropped onto, then the cells near Tulsa last night, it wouldn't surprise me again to see something similar.

[Nick F]

Yes, looks like a risk of strong tornadoes later from OK City Metro Area up through NE Oklahoma (including Tulsa Metro) and on into SW Missouri.

 

Central and NE Oklahoma lying in the right entrance of a strong 500mb W/SW'erly jet, so lots of mid-upper level divergence. 30knt+ 850mb southerly winds and surface winds backed towards SE which is going to create some strong wind shear. DPs forecast of 75F in central/NE Oklahoma yielding upwards 5000 j/kg CAPE. 

 

GFS and NAM breaking out precip just W and NW of OK City by 00z, towards/near dryline triple point. Just hope the large populated areas are spared later today, all the halmarks of strong tornado outbreak.

Edited May 31, 2013 by Nick F

[nsrobins]

RAP, whilst increasing deep layer EHI in C OK, has eased off the bulk shear and for this reason I am slightly less confident of significant tornados. The instability however is huge so very large, high-topped supercells are likely nethertheless.

The chase is on - and an active day lasting into the late evening is a given. I am going to go with Shawnee, OK because I wouldn't want to have to get past OKC from West to East at rush hour. That way I'd have room to push east with any cells towards Tulsa.
Storm motions today due east at 18-20mph.

[chionomaniac]

RAP, whilst increasing deep layer EHI in C OK, has eased off the bulk shear and for this reason I am slightly less confident of significant tornados. The instability however is huge so very large, high-topped supercells are likely nethertheless.

The chase is on - and an active day lasting into the late evening is a given. I am going to go with Shawnee, OK because I wouldn't want to have to get past OKC from West to East at rush hour. That way I'd have room to push east with any cells towards Tulsa.

Storm motions today due east at 18-20mph.

 

I think keeping out of the OK CITY metropolis area is a good call. I wouldn't want to be caught there. I think I would be happy on the Turner Turnpike east of OK City as well. Perhaps sit up around Chandler and see what comes my way!

[nsrobins]

There's contradictory opinions out there. The PWO is warranted and clearly indicates that although the potential is high, the risk of significant tornados is conditional. On the other hand the language on Stormtrack is bullish. The major event of last Monday was actually an isolated severe, long-track event in an otherwise 'standard' spread on the day. The same thing could happen again tonight. An isolated EF4+ out in open countryside won't make headlines. An EF4+ in the 'wrong' place (OKC or Tulsa metro for instance) is a completely different story. That's the principle that underpins the EF rating system, and makes forecasting these situations all the more difficult!

[robt]

Twitterspere this afternoon..

Jeff Piotrowski @Jeff_Piotrowski

Severe today i would upgrade central OK including OKC metro to High Risk per the 12Z high res data.

[Tom Lynch]

Hi all  I want check if the live stream is working    I shall turn it on for a short while    

 

We are currently in Ardmore

 

Tom

[icbinb]

Works fine Tom.

[Tom Lynch]

Thanks   I had it on yesterday and couldnt be sure that people could see it

 

Tom

[icbinb]

It was good for a lot of the evening, even though the status said offline.

[Stu Robinson]

I agree OKC as my target. Today is high risk for huge hail IMO. Moderate for Tornadoes..

[Tom Lynch]

Ok I will try to set status on line    will turn streaming on shortly       we will be heading through Moore 

 

Tom

just passed a house on its way to provide housing for the people in Moore

PLEASE NOTE I AM STUPID AND DO NOT KNOW HOW TO SET TO LIVE    SO JUST WATCh IT ANYWAY  IF ITS ON ITS ON :-)

Edited May 31, 2013 by Tom Lynch

[nsrobins]

I agree OKC as my target. Today is high risk for huge hail IMO. Moderate for Tornadoes..

High risk possible now for tornados too Stu as someone said earlier. Rapidly changing situation with latest guidance briging stroger LLJ over the top by 22Z.

Note: Stout cap fails at 20Z ish. Big loaded gun scenario off the dryline..

Latest SPC:

 

IT APPEARS THE THREAT OF A FEW STRONG/VIOLENT TORNADOES ARE IN PLACE.  HAVE INCREASED SEVERE

   PROBABILITIES OVER THIS REGION...AND PORTIONS OF CENTRAL/EASTERN OK

   WILL BE CONSIDERED FOR AN UPGRADE TO HIGH RISK AT 20Z IF

   SHORTER-TERM MESOSCALE MODELS MAINTAIN THIS SCENARIO.

 

 Watch the skies chaps (and model data, etc, of course!)

Edited May 31, 2013 by nsrobins

[Tom Lynch]

High Risk is possible for today, very possible     We will be having lunch in Norman   tank up and move west.

 

Tom

[Tom Lynch]

Change of plan . We are stopping or have stopped to eat in Paul's Valley     no comments please

 

Tom

[NL]

Just been following Mike Phelps on www.stormscapelive.tv and the last week he's had the chief forecaster for The Weather Channel chasing with him and on a telephone conversation with him in the last 10 mins he has had word from the SPC in Norman that the risk of tornadoes has increased to 30%. And the overall risk is to be upgraded to high risk in the next update.

[nsrobins]

Just been following Mike Phelps on www.stormscapelive.tv and the last week he's had the chief forecaster for The Weather Channel chasing with him and on a telephone conversation with him in the last 10 mins he has had word from the SPC in Norman that the risk of tornadoes has increased to 30%. And the overall risk is to be upgraded to high risk in the next update.

Not surprising. A potential PDS on this - looking significant as current obs and high-res models stand.

[Tom Lynch]

Ok folks we are on the move again    Heading towards Oklahoma City   will be passing though Moore on the way

 

Tom

[chionomaniac]

It's amazing how the upgrades in potential occur as we get closer to the time. A few days ago it looked like any potential for today would have cleared east and now we are looking at a high risk. Off out for the evening, so stay safe team, get lucky and let's hope that no populated areas get hit.

 

Ps edit already low 70's DP's in mid OK. I bet it feels steamy out there.

Edited May 31, 2013 by chionomaniac

[Tom Lynch]

Heading into into Moore in a  moment or two 

[nsrobins]

Thanks for the updates Tom. I repeat my advice, which I'm sure you are completely aware of, that the centre of the metro will be no place to be in a few hours. Sit just east or northeast - the cells will come to you in a more open environment with roads out of trouble.

[Tom Lynch]

thanks   for that I am sure Paul will take that on board   tom

[Tom Lynch]

traffic moving slowly through Moore

Paul or Ian        Verizon is connecting and disconnecting constantly   any suggestions

 

Tom

[samadamsuk]

Change of plan . We are stopping or have stopped to eat in Paul's Valley     no comments please

 

Tom

hahaha!