Thursday, June 2, 2011

DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 021725
SWODY2
SPC AC 021724

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1224 PM CDT THU JUN 02 2011

VALID 031200Z - 041200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE UPPER MS
VALLEY AND GREAT LAKES REGION...

...UPPER MS VALLEY/GREAT LAKES/MID-MO VALLEY/CNTRL PLAINS...
AN UPPER-LEVEL RIDGE WILL MOVE EWD ACROSS THE GREAT LAKES REGION
FRIDAY AS SOUTHWEST FLOW REMAINS ENTRENCHED ACROSS THE GREAT PLAINS
AND UPPER MS VALLEY. AT THE SFC...A COLD FRONT IS FORECAST TO MOVE
SEWD INTO MN WITH CONVECTION DEVELOPING AHEAD OF THE FRONT IN THE
WARM SECTOR FROM ERN MN SEWD ACROSS WI FRIDAY AFTERNOON. FORECAST
SOUNDINGS ACROSS THE WARM SECTOR AT 21Z FRIDAY SHOW A STRONGLY
UNSTABLE AIRMASS WITH MLCAPE VALUES IN THE 2500 TO 3500 J/KG RANGE.
THIS COMBINED WITH 45 TO 55 KT OF DEEP LAYER SHEAR WILL BE FAVORABLE
FOR SEVERE STORMS. THE STRONG DEEP LAYER SHEAR COMBINED WITH STEEP
MID-LEVEL LAPSE RATES WILL EASILY SUPPORT SUPERCELL DEVELOPMENT WITH
LARGE HAIL LIKELY WITH THE MORE ORGANIZED STORMS. A FEW TORNADOES
MAY OCCUR WITH THE MORE DOMINANT SUPERCELLS AS THE LOW-LEVEL JET
CONSOLIDATES AND STRENGTHENS DURING THE EARLY EVENING. FORECAST
SOUNDINGS INCREASE 0-3 KM STORM RELATIVE HELICITIES INTO THE 250 TO
350 M2/S2 RANGE BY EARLY EVENING SUGGESTING A THREAT FOR STRONG
TORNADOES COULD ALSO EXIST. A TRANSITION FROM DISCRETE CONVECTION TO
LINEAR MODE IS EXPECTED AS STORMS INCREASE IN COVERAGE AND LOW-LEVEL
FLOW STRENGTHENS. A QUICKER TRANSITION COULD RESULT IN AN ENHANCED
THREAT FOR WIND DAMAGE WITH THE GREATEST POTENTIAL ACROSS ERN WI AND
SRN LOWER MI FRIDAY EVENING.

FURTHER SOUTHWEST ACROSS THE CNTRL PLAINS...AN AXIS OF MODERATE
INSTABILITY SHOULD BE IN PLACE AHEAD OF A SEWD MOVING COLD FRONT.
AHEAD OF THE FRONT...A STRONG CAPPING INVERSION IS FORECAST IN THE
CNTRL PLAINS FOR MOST OF THE DAY. HOWEVER...FORECAST SOUNDINGS
AROUND 00Z ON SATURDAY...BRIEFLY WEAKEN THE CAPPING INVERSION WHICH
COULD ALLOW ISOLATED THUNDERSTORM DEVELOPMENT. MODERATE INSTABILITY
AND STRONG DEEP LAYER SHEAR WOULD SUPPORT A LARGE HAIL AND MARGINAL
WIND DAMAGE THREAT WITH ANY STORMS THAT CAN BECOME ROOTED IN THE
BOUNDARY LAYER.

...ERN GULF COAST STATES/SOUTH CAROLINA...
AN UPPER-LEVEL RIDGE IS FORECAST TO BE IN PLACE ACROSS THE MID-MS
VALLEY FRIDAY. MODERATE TO STRONG INSTABILITY SHOULD DEVELOP ACROSS
A VERY MOIST AIRMASS FROM THE UPPER-LEVEL RIDGE AXIS EWD ACROSS THE
TN VALLEY INTO THE ERN GULF COAST STATES. SOME MODEL FORECAST
DEVELOP SCATTERED THUNDERSTORMS ON THE ERN EDGE OF STRONGEST
INSTABILITY ACROSS GA AND SC FRIDAY AFTERNOON. IF STORMS DO
DEVELOP...THEN STEEP LOW-LEVEL LAPSE RATES AND 25 KT OF DEEP LAYER
SHEAR EVIDENT ON FORECAST SOUNDINGS...COULD BE ENOUGH FOR A MARGINAL
HAIL AND WIND DAMAGE THREAT.

..BROYLES.. 06/02/2011

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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: