DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 131707
SWODY2
SPC AC 131705

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1205 PM CDT THU JUN 13 2013

VALID 141200Z - 151200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE MID-MO
VALLEY...CNTRL PLAINS AND NRN PLAINS...

...MID-MO VALLEY/NRN AND CNTRL PLAINS...
AN UPPER-LEVEL RIDGE WILL BE IN PLACE ACROSS THE NRN AND CNTRL
PLAINS FRIDAY MORNING WITH A LOW-LEVEL JET LOCATED FROM CNTRL NEB
EXTENDING NWD INTO CNTRL ND. ELEVATED THUNDERSTORMS WITH A MARGINAL
SEVERE THREAT COULD BE ONGOING FRIDAY MORNING ALONG THE AXIS OF THE
LOW-LEVEL JET. THE MODELS MOVE THIS CONVECTION EWD INTO WRN MN
AROUND MIDDAY AS MODERATE TO STRONG INSTABILITY DEVELOPS ACROSS THE
ERN DAKOTAS FRIDAY AFTERNOON. SFC-BASED THUNDERSTORMS SHOULD DEVELOP
IN THE WAKE OF THE MORNING CONVECTION AS A COLD FRONT MOVES INTO THE
REGION FROM THE WEST. HOWEVER...CONVECTIVE COVERAGE IN THE ERN
DAKOTAS AND WRN MN SHOULD REMAIN ISOLATED DUE TO WARM AIR ALOFT AND
WEAK LARGE-SCALE ASCENT ASSOCIATED WITH THE UPPER-LEVEL RIDGE.

FORECAST SOUNDINGS AT OMAHA AND SIOUX FALLS AT 00Z/SAT SHOW MLCAPE
IN THE 2500 TO 3500 J/KG RANGE WITH 0-6KM SHEAR OF 45 TO 55 KT. THIS
ENVIRONMENT WILL LIKELY SUPPORT SEVERE THUNDERSTORM DEVELOPMENT AND
SUPERCELLS WILL BE POSSIBLE. THE STRONG INSTABILITY COMBINED WITH
STEEP MID-LEVEL LAPSE RATES SHOULD BE FAVORABLE FOR ISOLATED LARGE
HAIL WITH ANY STORM THAT CAN BECOME ESTABLISHED IN SPITE OF WEAK
LARGE-SCALE ASCENT. FORECAST SOUNDINGS ALSO SHOW VERY STEEP
LOW-LEVEL LAPSE RATES SUGGESTING A WIND DAMAGE THREAT MAY ALSO
DEVELOP. THE LIMITING FACTOR WILL BE THE WARM AIR ALOFT WHICH SHOULD
KEEP THE SEVERE THREAT COVERAGE ISOLATED DURING THE LATE AFTERNOON
AND EARLY EVENING.

FURTHER TO THE SOUTHWEST...MODERATE INSTABILITY SHOULD DEVELOP
FRIDAY AFTERNOON TO THE NORTH OF AN ELONGATED AND DEEPENING SFC LOW
FROM SCNTRL NEB EXTENDING SWWD INTO NE CO. MODEL FORECASTS DEVELOP
ISOLATED THUNDERSTORMS FRIDAY AFTERNOON ALONG THE NRN EDGE OF
MODERATE INSTABILITY AS A COLD FRONT APPROACHES. SOME OF THE MODELS
SUGGEST THAT CONVECTIVE COVERAGE WILL INCREASE IN THE CNTRL PLAINS
DURING THE EVENING AND OVERNIGHT PERIOD AS THE LOW-LEVEL JET
STRENGTHENS. DUE TO THE MODERATE INSTABILITY AND STEEP LAPSE
RATES...ANY CONVECTIVE CLUSTER WOULD PROBABLY HAVE AN ISOLATED
THREAT FOR WIND DAMAGE AND HAIL BEFORE BECOMING MARGINAL DURING THE
OVERNIGHT PERIOD.

...FL/SRN GA...
AN UPPER-LEVEL TROUGH WILL MOVE EWD FROM THE ATLANTIC SEABOARD TO
OVER THE GULF STREAM ON FRIDAY AS A COLD FRONT ADVANCES SEWD ACROSS
THE ERN GULF COAST STATES. THUNDERSTORMS APPEAR LIKELY TO DEVELOP
AROUND MIDDAY ALONG THE BOUNDARY ACROSS SRN GA AND NRN FL. MODERATE
INSTABILITY...STEEP LOW-LEVEL LAPSE RATES AND SFC DEWPOINTS IN THE
LOWER 70S F SHOULD BE ENOUGH FOR AN ISOLATED WIND DAMAGE THREAT
FRIDAY AFTERNOON.

..BROYLES.. 06/13/2013

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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.