Chase 2011 - Day 25 Discussion

[Paul Sherman]

This has all the hallmarks of being a very nasty situation today - Tornado Outbreak with Significant Tornadoes possible today.

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1259 AM CDT TUE MAY 24 2011

VALID 241200Z - 251200Z

...THERE IS A HIGH RISK OF SVR TSTMS ACROSS PARTS OF SOUTH CENTRAL

AND SOUTHEAST KANSAS SWD INTO PARTS OF CENTRAL AND EASTERN

OKLAHOMA...

...THERE IS A MDT RISK OF SVR TSTMS ACROSS CENTRAL AND SOUTHEAST

KANSAS...CENTRAL AND EASTERN OKLAHOMA...AND INTO WESTERN ARKANSAS...

...THERE IS A SLGT RISK OF SVR TSTMS FROM NEW ENGLAND SWD TO THE

MID-ATLANTIC REGION...AND WWD INTO THE PLAINS...

...SYNOPSIS...

WITH CYCLONIC FLOW ALOFT TO PERSIST ACROSS THE NORTHEAST U.S. AND

ERN CANADA...A STRENGTHENING MID-LEVEL SYSTEM -- ACCOMPANIED BY

70-PLUS KT MID-LEVEL JET -- IS FORECAST TO EMERGE INTO THE CENTRAL

AND SRN PLAINS. BY THE END OF THE PERIOD...A DEEPENING UPPER LOW IS

FORECAST ACROSS THE KS VICINITY -- WITH A 75 KT MID-LEVEL JET AROUND

THE SRN PERIPHERY OF THIS SYSTEM.

AT THE SURFACE...A COLD FRONT WILL CONTINUE ADVANCING ACROSS ERN

CANADA...MOVING EWD INTO NEW ENGLAND THROUGH THE AFTERNOON BUT

BECOMING MORE WASHED OUT ACROSS THE MIDWEST/OH VALLEY WITH TIME.

FARTHER W...A LEE LOW IS FORECAST TO MOVE VERY SLOWLY EWD/NEWD

ACROSS KS/OK...BUT SHOULD STRENGTHEN THROUGH THE AFTERNOON AS THE

UPPER LOW DEEPENS. BY LATE AFTERNOON...A DRYLINE WILL EXTEND SWD

ACROSS CENTRAL OK/CENTRAL TX AND A COMPOSITE WARM FRONT/OUTFLOW

BOUNDARY SHOULD EXTEND SEWD ACROSS SRN KS/ERN OK AND INTO AR. THIS

SURFACE SYSTEM WILL BECOME A FOCUS FOR THE DEVELOPMENT OF A

POTENTIALLY SIGNIFICANT SEVERE WEATHER OUTBREAK FOCUSED ON KS/OK/WRN

AR THROUGH THE AFTERNOON AND EVENING HOURS.

...CENTRAL AND SRN PLAINS...

A REGIONAL OUTBREAK OF SEVERE STORMS -- INCLUDING THE POTENTIAL FOR

VERY LARGE HAIL...DAMAGING WINDS...AND SEVERAL LARGE/STRONG

TORNADOES IS EXPECTED THIS AFTERNOON AND EVENING AS THE POWERFUL

UPPER JET EMERGES INTO THE PLAINS DRIVING SURFACE CYCLOGENESIS.

ELEVATED STORMS MAY BE ONGOING ACROSS PARTS OF NRN KS AND NEB AT THE

START OF THE PERIOD...WHILE A CAPPED WARM SECTOR HINDERS STORM

DEVELOPMENT INTO THE AFTERNOON HOURS. BY MID AFTERNOON...SURFACE

DEWPOINTS IN THE 60S TO NEAR 70 COMBINED WITH DAYTIME HEATING AND AN

EWD SPREAD OF VERY STEEP MID-LEVEL LAPSE RATES ATOP THE WARM SECTOR

WILL RESULT IN A VERY UNSTABLE ENVIRONMENT...WITH 100 MB MIXED-LAYER

CAPE VALUES EXCEEDING 3000 TO 4000 J/KG ACROSS PARTS OF OK/KS AND

INTO WRN AR E OF THE LOW/DRYLINE.

AS THE UPPER JET AND ASSOCIATED/DEEPENING UPPER SYSTEM EMERGE...A

SLOWLY WEAKENING CAP SHOULD RESULT IN STORM INITIATION BY LATE

AFTERNOON...FROM CENTRAL KS SWD INTO CENTRAL TX NEAR THE SURFACE LOW

AND SWD ALONG THE DRYLINE. WITH MODERATE/BACKED LOW-LEVEL FLOW

AHEAD OF THE SURFACE LOW VEERING AND INCREASING RAPIDLY THROUGH THE

LOWER TROPOSPHERE TO SWLY AT 50 TO 60 KT AT MID LEVELS...SHEAR VERY

SUPPORTIVE OF BOTH MID-LEVEL AND LOW-LEVEL ROTATION WILL ALLOW

STORMS TO RAPIDLY BECOME SUPERCELLULAR. VERY LARGE HAIL...DAMAGING

WINDS...AND SEVERAL POTENTIALLY SIGNIFICANT TORNADOES APPEAR LIKELY

AS THE STORMS INCREASE AND SPREAD ACROSS KS/OK INTO WRN AR AND THEN

LATER INTO WRN MO.

WHILE STORMS DEVELOPING SWD ACROSS CENTRAL TX ALONG THE DRYLINE

SHOULD EVENTUALLY BEGIN DIMINISHING DURING THE EVENING AS BOUNDARY

LAYER STABILIZATION/CAPPING BECOME REESTABLISHED...WIDESPREAD STORMS

AND ASSOCIATED SEVERE POTENTIAL WILL CONTINUE INTO THE OVERNIGHT

HOURS ACROSS KS/ERN OK/MO/AR. SLIGHTLY ELEVATED STORMS SHOULD ALSO

INCREASE INTO NEB/IA AND VICINITY...ALONG WITH SOME ACCOMPANYING

SEVERE THREAT.

[nsrobins]

Yep - need to be on your toes today for sure. Extrapolated deep layer shear (0 - H5) of up to 70kns as a strong upper jet streak pushes across the area. The one ingredient that's been short on supply lately is coming to town.

0-3km SRH of up to 500 develops in a region with 4000+ MLCAPE.

Somewhere along the I35 on the KS/OK border would be a reasonable starting point. With Tuscaloosa, Birmingham and Joplin already impacted this year, is Wichita about to be under the gun?

[chionomaniac]

No flat tyres needed today. Let's hope that the tornados miss the built up areas especially around Oklahoma City.

I hope that the refineries around Ponca City don't get hit as well.

[Cloud]

No flat tyres needed today. Let's hope that the tornados miss the built up areas especially around Oklahoma City.

I hope that the refineries around Ponca City don't get hit as well.

I was just admiring the forecast sounding for Ponca City, CAPE about 3000j/kg and 0-3km helicity about 500.

I think there could be major storm chaser convergence in southern Kansas/N Oklahoma.

[Gray-Wolf]

I hope you guys will play safe today! After the rain wrapped Joplin hit I get the heebie jeebies about multiple touchdowns combined with heavy rain.

[Nick F]

I like the look of south central Kansas for a chase target in the Comanche and Barber county areas. Looking at 06z NAM, good overlap of SBCAPE and strong wind shear across that area at the top of the dry line near triple point - where those surface winds will back. Only worry is that storms will quickly turn HP up here with associated risk of rain-wrapped tornadoes.

Also a bit further south down the dryline into north central Oklahoma maybe a better bet for more discrete supercells with still enough shear for tornadoes - if a distinct bulge develops along the dryline from the west across central Oklahoma, then potential for some strong tornadoes - worryingly in the OK City area too.

[gpspete]

my best guess I35 north of Oklahoma play day today perhaps east to Ponca City or similar position to drive towards oncoming storms for positioning quick look at this mornings models seem to show most simulated composite reflectivity over southern Kansas suspect the storm front may be quite stretched out today from Oklahoma City northwards will be lots of chaser hordes and storms today for definate what am i missing if i was there i would already be up at 5 waiting to go

[IanM]

I know the feeling Pete, it looks an incredible set up today. lets hope that whatever happens stays out on the plains and gives the guys plenty of action from the safety of tarmac roads.

I'd love to be there to chase, but if I was I suspect the models would change just as we reach the target area....

Safe chasing to you all, we'll be watching from the comfort of home

Ian

[Mesoscale]

Andy Gabrielson takes 3 spare tires!!! As hes always getting flats apparently.

Could be some violent tornadoes today stay safe!

[nsrobins]

Current elevated convection affects conditions C KS? Will it clear in time for that area to recover. I might wander a bit south to far N C OK. RUC initiates cell at 22Z here.

[duckeyh]

<expleative> I'm gonna say it even though it cursed T1.. Stay Safe Guys

[icbinb]

Well, based on my last two days of awful targets, the area for the team to avoid like the plague is Wellington, Kansas. Have fun and stay safe.

Edit- Purely based on the cloud cover I would get myself down into Western Oklahoma where it is clear at the moment, maybe somewhere like Weatherford.

[multi cellular thunderstorm]

I'm very jealous of tour 3 getting all this action, but good luck and be safe and get plenty of pics and video for us all to admire.

I guess there is a very excitable atmosphere over there this morning, Paul has probably been up for many hours now going over the models.

I think I would give my whole 10 days of tour 1 for the day you are about to hopefully have!

Hope any tornadoes today stay in the fields and away from built up areas. I keep thinking about poor Joplin, how normal it was when we were there compared to how it must be now.

[chionomaniac]

I'm very jealous of tour 3 getting all this action, but good luck and be safe and get plenty of pics and video for us all to admire.

I guess there is a very excitable atmosphere over there this morning, Paul has probably been up for many hours now going over the models.

I think I would give my whole 10 days of tour 1 for the day you are about to hopefully have!

Hope any tornadoes today stay in the fields and away from built up areas. I keep thinking about poor Joplin, how normal it was when we were there compared to how it must be now.

No harm in being jealous - I am too! Has Paul chucked the red cap away yet - it is the tornado deflection device.

Keep safe and keep those toilet stops to a minimum!

My Target is Ponca City.

[Gorky]

Anyone got a map with a higher EHI scale on? :o

Link

Last time I saw such a large area maxed out on these maps was April 27th....

[Paul Sherman]

Yep N Central Oklahoma and S Central Kansas for us. Scary looking charts at the moment. They are ramping this up big time here telling people to have an action plan for 3-10pm today.

Gotta be careful where we end up tonight as well, lines of Supercells with risk of Tornadoes sweeping east overnight as well.

Tipped off that tomorrow could also be High Risk as well.

Thank god the Michaelwaite Storm Shield has gone home :lol: Only joking Ian!

Not taking any risks today

[nsrobins]

Loads to ponder over your breakfast 9if not on the road already).

There's some subtle features that will need to be taken into account that could make the difference between being on the money or being half an hour away.

1) WEAK W-E BOUNDARY NOW INVOF THE RED RVR SHOULD MOVE/REDEVELOP NEWD LATER TODAY

Umm - not sure of this one but may prove interesting as it's western end interacts with the DL

2) OUTFLOW BOUNDARY FROM THIS FEATURE MAY SERVE AS A FOCUS FOR STORM DEVELOPMENT IN CNTRL/ERN KS LATER TODAY

This is the elevated stuff exiting stage left as we speak. Some moderation of surface moisture yes but a decent OFB and you have another trigger point up in S C KS.

Those progged EHIs are insane (14+ can that be right)

Hold on tight please and keep seatbelts tightly fastened at all times.

[IanM]

Thank god the Michaelwaite Storm Shield has gone home :lol: Only joking Ian!

Not taking any risks today

I told you it would happen, I'm going to start charging counties $10K a day to visit and keep them under blue skies, regardless of the SPC forecast, I'll make a fortune! You can take the tour guests anywhere other than where I am for some decent storms too, it's a win/win situation.....

[gpspete]

No harm in being jealous - I am too! Has Paul chucked the red cap away yet - it is the tornado deflection device.

Keep safe and keep those toilet stops to a minimum!

My Target is Ponca City.

strong updraft today will remove said cap and the great tornado god will take possession of it

[nsrobins]

Found this rather nicely worded piece by Greg Forbes (coutesy The Weather Channel)

http://www.weather.com/outlook/weather-news/news/articles/tornado-outbreak-tue-classic-ingredients_2011-05-23

[Harry]

My feeling for today is somewhere in the triangular zone between Arkansas City, Wichita and Eureka (all KS)...maybe Rose Hill as she could be a distant relative of mine lol

Best of luck guys! Am soooooooooo jealous I could not go this year!

Stay safe but EVEN more important than that, have a bloody good time

Lots of nice photos/vids please!

[Supercell]

Yep N Central Oklahoma and S Central Kansas for us. Scary looking charts at the moment. They are ramping this up big time here telling people to have an action plan for 3-10pm today.

Gotta be careful where we end up tonight as well, lines of Supercells with risk of Tornadoes sweeping east overnight as well.

Tipped off that tomorrow could also be High Risk as well.

Thank god the Michaelwaite Storm Shield has gone home :lol: Only joking Ian!

Not taking any risks today

Really wishing I was back with you right now. Had a few gusts of 30 mph yesterday and a 2mm of rain

[Paul Sherman]

Just been outside and it has that ominous feel today. Moisture screaming Northwards on a strong southerly, very moist unstable air, clearing already along the dryline in Western Oklahoma. Going to leave at 1130am and head to Enid for lunch and Gassing up the cars with a full tank.

Paul S

[Biggin]

Hi, A newbie to the chase thread, Good luck people, but stay safe. Stream was jerky and stalling for me last night, but other chasers streams were ok, any suggestions??

Paul any chance of some breakfast pictures if you get time??

[chionomaniac]

Dew points seem to be highest over the clear air.

Very ominous for when the temperature rises.