Chase 2010 - Day 15 Discussion

[Paul Sherman]

Another day another Risk for Tour 2!

Looks like a Dryline and Stalled Warm Front again with Storms expected in the TX & OK Panhandle and also across Southern Kansas. SPC Go with a 5% Tornado Risk and thankfully Storm Motions will not go at Rocket Speeds today!

Paul S & Team

[Harry]

Slower storms, always good news And hopefully making for some more great pics and vids!

Best of luck as ever chaps - stay safe but EVEN more importantly, have a wicked time

[Gorky]

Heading to the SW OK area myself today,and perhaps across into TX near Wichita Falls. Extreme Cape values again should lead to some explosive storms. A 2% tor risk only for the area but you get some good results on 2% days quite often!

[Nick F]

Only just had chance at the models for today's prospects, 12z RUC shows some extreme CAPE (6000 j/kg) over large parts of Oklahoma at 00z (18z CDT):

12z Norman sounding (which is 6am local CDT) shows lots of CAPE (and strong cap) even this early in the morning, though I think RUC seems a little OTT.

Best 0-3km SR Helicity values seem to be towards NW Oklahoma, this is also near stalled warm/cold front:

Either play the dry line towards SW/W Oklahoma or play the stalled front over NW Oklahoma. I fancy heading to Woodward, OK to utilise best wind fields, though part of me wants to play the dry line over SW OK.

[Nick F]

RUC breaks out convective precip W/NW of OK City around Watonga area by 00z (18z CDT), so this area could be perhaps an area to target based on models, certainly in an environment of strong SR helicity:

[Dorsetbred]

Found this whilst cruising through the threads on stormtrack.org

"A chasing tour got a direct hit today. Apparently this is because of a crazy chaser convergence with some chasers blocking the road. People got injured because of this"

Has to a major concern with what is now becoming extremely popular weather watching event...

Edited May 11, 2010 by Dorsetbred

[Nick F]

Found this whilst cruising through the threads on stormtrack.org

"A chasing tour got a direct hit today. Apparently this is because of a crazy chaser convergence with some chasers blocking the road. People got injured because of this"

Has to a major concern with what is now becoming extremely popular weather watching event...

Aye, the plains are probably the busiest they have ever been with chasers, programmes such as Storm Chasers on Discovery Channel with the exploits of Sean Casey and Reed Timmer only serve to whet the appetites of more budding chasers. However, some courtesy and common sense is perhaps needed by some chasers to avert problems of safety where chasers are caught out by chaser congestion on roads near storms - with escape routes blocked. Trouble is, a growing number are out there for themselves to get the best footage possible, regardless of thought for others and of whether they maybe causing an obstruction and danger to other road users.

[John Hanrahan]

Found this whilst cruising through the threads on stormtrack.org

"A chasing tour got a direct hit today. Apparently this is because of a crazy chaser convergence with some chasers blocking the road. People got injured because of this"

Has to a major concern with what is now becoming extremely popular weather watching event...

I have not seen the thread yet, but I'm pretty sure they were referring to Vortex 2 which have been known to block junctions to allow their armada through.

[Paul]

Team just finishing lunch and will be on the move soon:

http://www.netweather.tv/index.cgi?action=chaselive;sess=

[NL]

Meso- discussion from NWS spc concerning severe potential.

MESOSCALE DISCUSSION 0517

NWS STORM PREDICTION CENTER NORMAN OK

0224 PM CDT TUE MAY 11 2010

AREAS AFFECTED...NWRN TX THROUGH SWRN AND W-CNTRL OK

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 111924Z - 112130Z

NWRN TX THROUGH SWRN AND W CNTRL OK ARE BEING MONITORED FOR STORM

INITIATION. IF THUNDERSTORMS DEVELOP THEY WILL RAPIDLY INTENSIFY AND

BECOME SUPERCELLULAR WITH VERY LARGE HAIL AND TORNADOES PROBABLE.

A WARM FRONT STRETCHES FROM SRN MO SWWD THROUGH CNTRL OK THEN WW

INTO THE TX PANHANDLE. A DRYLINE EXTENDS THROUGH WRN AND NWRN TX

INTO SWRN OK WHERE IT INTERSECTS THE DRYLINE. PARTIAL CLEARING HAS

OCCURRED IN PORTION OF WARM SECTOR FROM NWRN TX THROUGH WRN OK

BOOSTING TEMPERATURES TO AROUND 80...AND OBJECTIVE ANALYSIS SHOWS A

RESERVOIR OF 4000 J/KG MLCAPE WHERE STEEP MID-LEVEL LAPSE RATES HAVE

OVERSPREAD THE THETA-E AXIS. THE SCALLOPED APPEARANCE OF THE LOW

CLOUDS AND POINT FORECAST SOUNDING DATA SUGGEST THE BOUNDARY LAYER

IS STILL CAPPED...AND UNCERTAINTY EXISTS REGARDING THE EXTENT AND

TIMING OF INITIATION. HOWEVER...THE LOW LEVEL JET WILL STRENGTHEN

TOWARDS EVENING...AND THIS WILL ENHANCE CONVERGENCE AND ISENTROPIC

LIFT ALONG AND JUST NORTH OF THE WARM FRONT. WV IMAGERY ALSO

SUGGESTS A SHORTWAVE TROUGH MAY BE MOVING EWD THROUGH WRN TX...AND

DEEPER ASCENT ASSOCIATED WITH THIS FEATURE COULD PROMOTE

THUNDERSTORM DEVELOPMENT FARTHER S OVER NWRN TX ALONG THE DRYLINE.

GIVEN THE EXTREME INSTABILITY...40-50 KT DEEP LAYER SHEAR AND

INCREASING 0-1 KM HODOGRAPH SIZE WITH TIME...SUPERCELLS WITH VERY

LARGE HAIL AND A FEW TORNADOES WILL BE LIKELY...CONDITIONAL UPON

INITIATION.

[NL]

If initiation transpires i feel the risk will go to Moderate Risk all depends on the wind profiles as moisture and instability are excellent.

Latest visible satellite image.

[nsrobins]

A bit late on this one as been really busy all day and now watching the shenanigans with David Cameron arriving at Number 10 in the last few minutes.

The latest RUC CAPE and SRH parameters are insane for 22Z and the cap looks like being breached between 22Z and 22.30Z in W OK. I would be setting up around Clinton, OK which admittedly looks a tad east of the DL but in an area of insane 6000+ CAPE. I would be interested if there are any subtle boundaries in the area which may help focus on the likely initiation target.

[Paul]

Woohoo, clean windscreen :lol:

[Gorky]

I'm sat in Hobart at the moment, really just checking out the terrain down here before this afternoons storms. I expect initiation west of here near the TX border once the dryline sharpens. Sat under a CU deck at the moment, but it's not showing any sign of breaking the cap at the moment and I think we'll need the forcing at the dryline to do that. I expect I'll be heading north back to Sayre or Elk City shortly and await initiation up there. Today could be manic with only isolated storms. I expect that could lead to every chaser being on the same one!

[NL]

Woohoo, clean windscreen

Yeah... I thought they were getting a helicopter escort...!!!:lol:

I just put the stream on full-screen and the 'escort' helicopter is still there..!! Sack the windscreen cleaner..!!

Edited May 11, 2010 by NL

[Gorky]

oh..and it feels like an absolute sauna outside at the moment...

[nsrobins]

What's you're thinking behind looking at a more southern target, Paul? I had a look at the possible impulse SPC were on about and WV imagery does indeed show a sharp dry slot now crossing the TX panhandle which could be the forcing required for initiation on or just north of the Red River.

[Roger J Smith]

I like the team's current position and feel that severe storms will develop soon between Andarko and El Reno OK. This is basically a warm frontal wave being energized by anti-cyclonic energy rotation of the J-field which peaks around 23z. It may not be very mobile, cells may tend to hang around where they form. Could be just TRW+ non-severe but these large cells can drop a tornado fairly easily. Tomorrow looks juicy in KS.

[SnowBear]

Everyone in Chickasha owns a damn pick up, not a car in sight! lol

[NL]

Tornado watch..

890

WWUS20 KWNS 112048

SEL1

SPC WW 112048

OKZ000-TXZ000-120300-

URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 151

NWS STORM PREDICTION CENTER NORMAN OK

350 PM CDT TUE MAY 11 2010

THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF

WESTERN OKLAHOMA

WESTERN NORTH TEXAS

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 350 PM UNTIL

1000 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES NORTH AND SOUTH OF A LINE FROM 10 MILES SOUTHEAST OF

CHICKASHA OKLAHOMA TO 45 MILES WEST NORTHWEST OF ALTUS OKLAHOMA.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS.

DISCUSSION...ISOLATED SUPERCELL THUNDERSTORMS ARE EXPECTED TO

DEVELOP THIS AFTERNOON AND EVENING NEAR RETREATING DRYLINE...WHERE

STRONG HEATING HAS YIELDED EXTREME INSTABILITY. INCREASING VERTICAL

WIND SHEAR THROUGH THE EVENING WILL ENHANCE THE RISK OF VERY LARGE

HAIL AND TORNADOES.

Lates vis sat image..

Edited May 11, 2010 by NL

[NL]

Hazard watch probabilities from the SPC have 50% moderate probability of 2 or more tornadoes and 30% moderate probability of 1 or more strong tornadoes (EF2-EF5.)

[Paul]

Team have parked up, so guess it's now the waiting game to see what kicks off where.

Live stream:

http://www.netweather.tv/index.cgi?action=chaselive;sess=

[Nick F]

I'm quite liking the Altus to Sayre/I-40 area in far western Oklahoma for intiation, large bullseye of CAPE, highest temps and largest pressure falls here on hourly mesoanalysis and we have a dryline/warm front intersect in this area:

Though best SR Helicity is best towards NW/N OK, so maybe ending up just north of I-40 for best posibilities of a tornado from storms that form off the dryline or along the warm front drifting north towards KS border:

[the storm fisherman]

hi all

as i have internet connection i can add a couple of points of intrest

i am waiting at clinton,ok for the cap to go pop, the tour that got munched was by a vortex that pushed one roger hill of the road and blew all the windows out same time. as far as i know there were no casulty's

[Gorky]

Still sat in Hobart. Watching the CU bubble up and down. They are making a real go of it right now. Shouldn't be too long before initiation now I don't think