Thursday, October 9, 2008

DAY2SVR: Nws Storm Prediction Center Norman Ok

ACUS02 KWNS 091727
SWODY2
SPC AC 091724

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1224 PM CDT THU OCT 09 2008

VALID 101200Z - 111200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
AMPLIFICATION OF THE UPPER FLOW PATTERN IS NOW WELL UNDERWAY...WITH
A RIDGE BUILDING OVER THE EASTERN PACIFIC...AS A TROUGH DEEPENS OVER
THE WESTERN UNITED STATES. CONSIDERABLE AGREEMENT EXISTS AMONG
MODEL GUIDANCE CONCERNING SUBSEQUENT EVOLUTION THROUGH FRIDAY/FRIDAY
NIGHT...INCLUDING THE DEVELOPMENT OF A FAIRLY DEEP LOW/MID-LEVEL
CYCLONE OVER THE CENTRAL/SOUTHERN GREAT BASIN AND A DOWNSTREAM
SURFACE TROUGH ACROSS THE GREAT PLAINS. AN UPPER RIDGE IS PROGGED
TO BUILD DOWNSTREAM ACROSS MUCH OF THE SOUTHERN/EASTERN
STATES...FORCING A WEAKENING CUT-OFF LOW OFF THE SOUTH ATLANTIC
COAST.

MODELS INDICATE THAT PHASING WILL OCCUR BETWEEN THE AMPLIFYING
WESTERN TROUGH AND A STRENGTHENING SOUTHERN OR SUBTROPICAL STREAM.
AND...THIS APPEARS LIKELY TO BE ACCOMPANIED BY A NORTHWARD FLUX OF
LOW-LEVEL AND MID/HIGH-LEVEL MOISTURE FROM THE LOWER LATITUDE
EASTERN PACIFIC...AND THE DEVELOPING STAGES OF A SIGNIFICANT RETURN
FLOW OFF THE WESTERN GULF OF MEXICO. WHILE MOISTENING WILL PROBABLY
LEAD TO INCREASING CONVECTIVE POTENTIAL ACROSS PARTS OF THE WESTERN
AND CENTRAL STATES DURING THE COMING DAYS...WEAK DESTABILIZATION
THROUGH THIS FORECAST PERIOD IS EXPECTED TO MAINTAIN FAIRLY LOW
THUNDERSTORM PROBABILITIES ACROSS MOST AREAS.

...MEXICAN PLATEAU INTO THE SOUTHERN ROCKIES...
MOISTURE RETURN COUPLED WITH FAVORABLE LARGE-SCALE ASCENT...AND
OROGRAPHIC FORCING ACROSS THE MOUNTAINS OF SOUTHEASTERN ARIZONA AND
SOUTHERN NEW MEXICO...PERHAPS NORTHWARD INTO PARTS OF SOUTHERN
COLORADO...LIKELY WILL RESULT IN AT LEAST WIDELY SCATTERED
THUNDERSTORMS BY LATE FRIDAY AFTERNOON OR EARLY EVENING. SUFFICIENT
INSTABILITY MAY BE MAINTAINED ACROSS SOUTHEASTERN
ARIZONA/SOUTHWESTERN NEW MEXICO FOR CONTINUING ACTIVITY INTO/
THROUGH THE OVERNIGHT HOURS.

...PLAINS...
WITH SUBSTANTIAL LOW-LEVEL MOISTENING NOT LIKELY TO OCCUR ACROSS
MUCH OF THE PLAINS PRIOR TO 12Z SATURDAY...CONVECTIVE POTENTIAL IS
EXPECTED TO REMAIN CONFINED TO A QUASI-STATIONARY LOWER/MID LEVEL
FRONTAL ZONE FROM THE NORTH CENTRAL HIGH PLAINS THROUGH THE EASTERN
DAKOTAS AND NORTHERN MINNESOTA. ENHANCED ASCENT AND DESTABILIZATION
WITHIN A WARM ADVECTION REGIME ON THE NOSE AN ELEVATED MIXED LAYER
MAY CONTRIBUTE TO PERIODS OF SCATTERED THUNDERSTORM ACTIVITY
THROUGHOUT THE PERIOD.

...FLORIDA...
THE SLOWLY WARMING MID-LEVEL COLD CORE OF THE CUT-OFF LOW IS
EXPECTED TO SHIFT OFF THE SOUTH ATLANTIC COAST...NORTHEAST OF THE
PENINSULA EARLY IN THE PERIOD. BUT...LOW-LEVELS APPEAR LIKELY TO
REMAIN MOIST ENOUGH...AND INHIBITION WEAK ENOUGH...TO ALLOW
SCATTERED THUNDERSTORM ACTIVITY...PARTICULARLY ACROSS EASTERN/
SOUTHERN PORTIONS OF THE PENINSULA DURING THE LATE AFTERNOON/EARLY
EVENING HOURS.

..KERR.. 10/09/2008

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