Chase 2010 - Day 13 Discussion

[Paul Sherman]

The day before the BIG Day and the new guys might get to see some marginally Severe Hailers today. The main objective is to keep the main focus on the expected High Risk for Monday and not to get ourselves out of place. So I am expecting a few late High Based Storms maybe over parts of Oklahoma or Kansas for the new guys to cut their teeth on. Still looking good for Oklahoma or Kansas for a possible Outbreak on Monday.

Paul S

[Nick F]

Moderate Risk atm, but I expect it will go high with 45% probabilities - with risk of long-track strong tornadoes.

DAY 2 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1236 AM CDT SUN MAY 09 2010

VALID 101200Z - 111200Z

...THERE IS A MDT RISK OF SVR TSTMS ACROSS NCNTRL/NE OK...SCNTRL/SE

KS AND EXTREME SW MO...

...THERE IS A SLGT RISK OF SVR TSTMS FROM THE CNTRL/SRN PLAINS TO

THE MID-MS VLY...

***SUPERCELLS WITH LONG-TRACK STRONG TORNADOES AND VERY LARGE HAIL

EXPECTED MONDAY LATE AFTN/EVENING ACROSS PARTS OF CNTRL/N OK...SE KS

AND SW MO***

...CNTRL/SRN PLAINS TO THE MID-MS VLY...

WATER VAPOR SHOWS A HEALTHY MID-LVL SHORTWAVE TROUGH APPROACHING THE

CNTRL/NRN CA COAST SUNDAY MORNING. FEATURE WILL REACH THE

FOUR-CORNERS REGION MONDAY MORNING AND THE CNTRL/SRN PLAINS BY

EVENING. SFC LOW WILL INTENSIFY OVER SCNTRL KS MONDAY AFTN BEFORE

TRANSLATING TO N MO BY 12Z TUESDAY. TO THE S OF THE LOW...A DRYLINE

WILL MIX EWD INTO SCNTRL KS AND WRN PARTS OF TX/OK DURING THE AFTN

AND BE THE IMPETUS FOR TSTM INITIATION.

THERE STILL REMAINS A SLIGHT AMOUNT OF UNCERTAINTY WITH RESPECT TO

TROUGH TIMING/SFC FEATURE PLACEMENT AND GFS REMAINS ON THE ERN EDGE

OF THE ENVELOPE OF SOLUTIONS. CANNOT DISCOUNT THAT IDEA COMPLETELY

GIVEN HOW MOBILE/ZONAL THE FLOW REGIME WILL BECOME IN THE NEXT 24-48

HOURS AND CURRENT DAY 2 OTLK WILL INCLUDE ELEMENTS OF BOTH 00Z

NAM/GFS...MOST LIKE THE 12Z ECMWF.

ELEVATED CONVECTION...WHICH MAY ALREADY BE PRODUCING LARGE HAIL

ACROSS PORTIONS OF OK AND ERN KS MONDAY MORNING...SHOULD MOVE ENE

TOWARD THE MID-MS VLY DURING THE AFTN. AIR MASS SHOULD RECOVER

RAPIDLY IN WAKE OF THESE STORMS WITH MONDAY AFTN MID-60S SFC DEW

POINTS SURGING NWD THROUGH OK AND INTO SCNTRL KS. CINH...RATHER

STRONG INITIALLY...SHOULD WEAKEN WITH THE APPROACH OF DCVA...

DEEPENING DRYLINE CIRCULATION AND STRONG HEATING. TSTM INITIATION

WILL OCCUR MID-LATE AFTN...MOST LIKELY IN SCNTRL KS AND NCNTRL

OK...WITH MORE ISOLD STORMS FARTHER S ALONG THE LENGTH OF THE

DRYLINE INTO SWRN OK AND W TX.

AS STORMS MOVE OUT OF THE DRYLINE CIRCULATION...LARGELY

PERPENDICULAR DEEP-LAYER WIND VECTORS...MLCAPES TO 3000 J/KG AND

EFFECTIVE SHEAR 50-70 KTS WILL FAVOR DISCRETE SUPERCELLS WITH VERY

LARGE HAIL. FCST HODOGRAPHS EXHIBIT VERY STRONG LOW-LEVEL SRH IN

EXCESS OF 400 M2/S2 AND GIVEN ANTICIPATED STORM MODE...INCREASE IN

THE NOCTURNAL EVENING LLJ AND LOWERING LCL/S...LONG-TRACK STRONG

TORNADOES WILL BE POSSIBLE... PARTICULARLY FROM OK PORTION OF

I-40/44 NWD INTO SCNTRL/SERN KS DURING THE EARLY EVENING.

WARM SECTOR WILL RAPIDLY RECOVER DOWNSTREAM OF EARLY EVENING

ACTIVITY INTO SWRN MO AND SET-UP APPEARS CONDUCIVE TO SUPPORT

DISCRETE SUPERCELLS WELL INTO THE EVENING. EVENTUALLY...ACTIVITY

WILL TRANSITION INTO LINES/CLUSTERS OVERNIGHT WITH DMGG

WINDS...ISOLD TORNADOES AND LARGE HAIL PROBABILITIES AS FAR E AS THE

MID-MS RVR VLY BY 12Z TUESDAY.

FARTHER S...SUPERCELLS THAT MAY FORM ACROSS SW OK INTO W TX WILL

DIMINISH DURING THE EARLY EVENING AS STRONGER FORCING EXITS TO THE N

OF THE REGION.

[CardiffStorm]

***SUPERCELLS WITH LONG-TRACK STRONG TORNADOES AND VERY LARGE HAIL

EXPECTED MONDAY LATE AFTN/EVENING ACROSS PARTS OF CNTRL/N OK...SE KS

AND SW MO***

I'll be watching the live streaming then

[plymouthflye]

Moderate Risk atm, but I expect it will go high with 45% probabilities - with risk of long-track strong tornadoes.

Oh well, another night the missus is on her own while i'm up watching the stream. Priorities!

Seriously, i am really looking forward to this chase.

Take care guys, and hope you all enjoy your tour.

[Harry]

Appears a few cells are trundling towards SW OK, could be an exciting first proper night for the chaps!

Hope to get see some piccies :blush:

[Paul]

Hope you had a decent trip home Harry!

Team have arrived at their hotel in Norman OK, cells containing some storms/hail are heading toward them and not too far off... Live stream currently online

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

[dogs32]

few storms heading this way with large hail for later..

and tomorrow looks awesome :blush:..with long lived tornados

WEATHER channel predicting Outbreak

Edited May 9, 2010 by dogs32

[user700]

Hi, we are at Norman Oklahoma this is the latest radar!

[Paul Sherman]

Some VERY Strong Wording both on the SPC & Weather Bulletins for tomorrow, this is going to be a very dangerous day and I hope major towns and cities are not in the path of this as it could be Newsworthy!

Paul S

[nsrobins]

Indeed Paul - any chance of an early Discussion thread for Day 14.

Just posted this on UKWW:

I sort of suspected the moisture feed would recover from the modelled values of yesterday and the 18Z NAM returns 65F into W C OK ahead of a very well-defined DL. Crazy deep EHI values just west of OKC at 21Z say long-lived mesos to me and I might be tempted to set-up on the I35 corridor and intercept rather than chase as the convergence is going to to be hell TBH. The OKC sounding for the same time shows nearly 90degree turn from surface to 850mb so it's pretty much a given that any cell moving off the boundary will turn like crazy and stay that way for a fair time.

Take care chaps.

[Paul]

Team heading over to the SPC to take a look, storm cells edging closer too....

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

[Stuart]

dont think Doppler Radar working

[dogs32]

sky looks nasty here at times..

slightly warmer over the last hr...

Hopeful for some severe storms later as the Jet kicks in..

a few deep echoes on radar appearing..

a few svere Thunderstorms reports on NOA with large hail

Edited May 9, 2010 by dogs32