Thursday, May 13, 2010

DAY1SVR: Day 1 Convective Outlook

ACUS01 KWNS 130524
SWODY1
SPC AC 130523

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1223 AM CDT THU MAY 13 2010

VALID 131200Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE
MIDWEST/OH VLY...

...SYNOPSIS...
UPR TROUGH MOVING ACROSS THE CNTRL/SRN PLAINS EARLY THURSDAY WILL
CONTINUE ENE INTO THE GRTLKS REGION BY NIGHTFALL AS ADDITIONAL
ENERGY DIGS INTO THE GRT BASIN/CNTRL ROCKIES. THE ASSOCIATED SFC
LOW INITIALLY OVER NRN MO WILL MOVE INTO ERN WI BY EVENING AND INTO
THE CNTRL GRTLKS BY 12Z FRIDAY. A TRAILING CDFNT...AUGMENTED BY
TSTM OUTFLOW...WILL SETTLE SEWD INTO THE MIDWEST...LWR OH VLY AND
SRN PLAINS THROUGH THE PERIOD.

...MIDWEST/OH VLY...
RATHER WIDESPREAD CONVECTION...LARGELY ELEVATED...WILL BE ONGOING AT
12Z THURSDAY OVER THE CNTRL GRTLKS REGION AND UPR MIDWEST. THIS
ACTIVITY WILL CONTINUE NWD THROUGH THE GRTLKS DURING THE DAY. IN
ITS WAKE...MOIST BOUNDARY LAYER OVER THE OH VLY WILL SURGE AS FAR N
AS NRN IL AND SRN LWR MI. LAPSE RATES WILL REMAIN MODEST...BUT SOME
HEATING COMBINED WITH RELATIVELY MOIST BOUNDARY LAYER WILL BOOST
MLCAPES 1500-2000 J/KG RANGE. AS SRN FRINGE OF THE EJECTING UPR
TROUGH GRAZES THE REGION...TSTMS SHOULD READILY FORM ALONG/AHEAD OF
THE APPROACHING CDFNT/OUTFLOW BOUNDARIES FROM IL INTO SERN MO.
VERTICAL SHEAR 45-50 KTS WILL BE FAVORABLE FOR SUPERCELLS...ALTHOUGH
EVOLUTION INTO LINES/BOWS IS LIKELY WITH PRIMARY THREATS BEING DMGG
WINDS AND A COUPLE OF TORNADOES... PRIMARILY ACROSS CNTRL/NRN IND
INTO OH WITHIN A CORE OF 40-50 KTS OF MID-LVL WLY FLOW. ACTIVITY
WILL DIMINISH GRADUALLY OVERNIGHT.

...TX...
A MCS OR TWO SHOULD BE ONGOING AT THE START OF THE PD OVER PARTS OF
OK AND NW TX. A COUPLE STORMS MAY BE PRODUCING LARGE HAIL OR DMGG
WIND GUSTS. THIS ACTIVITY WILL LIKELY WEAKEN DURING THE MORNING AS
SLY LLJ BEGINS TO WEAKEN WITH PASSAGE OF THE UPR TROUGH. IN THE
WAKE...AIR MASS ALONG/S OF THE OUTFLOW BOUNDARY/DECELERATING CDFNT
WILL REMAIN MOIST AND UNSTABLE WITH SFC DEW POINTS WELL IN THE
60S/LWR 70S AND MID-LVL LAPSE RATES 6.5-7 DEG C/KM. SFC-BASED
STORMS WILL REMAIN POSSIBLE WHERE STRONG HEATING CAN MATERIALIZE
OVER CNTRL TX DURING THE AFTN. BUT...LARGE SCALE HEIGHT RISES AND
WEAKENING DEEP LAYER/LLVL SHEAR WILL TEND TO KEEP STORM ORGANIZATION
ISOLD. IF STORMS CAN FORM...STRONG WINDS/HAIL MAY OCCUR. LATER
OTLKS WILL ADDRESS POTENTIAL FOR HIGHER COVERAGE AND POSSIBLE SLGT
RISK.

..RACY/ROGERS.. 05/13/2010

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.

No comments: