SWODY2
SPC AC 170548
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1248 AM CDT SUN OCT 17 2010
VALID 181200Z - 191200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
UPPER AIR PATTERN THIS PERIOD FCST TO FEATURE TROUGHING OVER UPPER
MIDWEST/GREAT LAKES REGIONS...AND CUT-OFF LOW JUST OFF CENTRAL/SRN
CA COAST. LATTER LOW IS EXPECTED TO MOVE SLOWLY SEWD TOWARD NRN
BAJA THIS PERIOD...REFLECTING STG CONSENSUS NOW PRESENT AMONG
OPERATIONAL/DETERMINISTIC PROGS AND SREF MEMBERSHIP.
MEANWHILE...SERIES OF LOW-AMPLITUDE SHORTWAVES IS FCST TO TRAVERSE
CYCLONIC FLOW ACROSS NRN PLAINS...GREAT LAKES AND MID-ATLANTIC
REGIONS. AS THIS OCCURS...HEIGHTS WILL FALL ACROSS CENTRAL
PLAINS...OZARKS AND OH VALLEY REGIONS. SFC FRONT...FCST TO
DEVELOP/INTENSIFY OVER CENTRAL PLAINS...MO AND KY DAY-1...IS
EXPECTED TO MOVE SWD ACROSS W TX...OK AND OZARKS DAY-2 AS COLD
FRONT.
...WRN CONUS...
BROAD REGIME OF DIFLUENT FLOW AND AREAS OF UPPER DIVERGENCE ARE FCST
DOWNSTREAM FROM PAC LOW...BENEATH AND N OF EXIT REGION OF 250 MB JET
THAT WILL REMAIN LARGELY S OF MEX BORDER. RELATED/WEAK LARGE-SCALE
ASCENT SHOULD COMBINE WITH LOW-LEVEL DIABATIC HEATING/MIXING TO
YIELD BROAD SWATH OF STEEP DEEP-LAYER LAPSE RATES BY MID-LATE
AFTERNOON. WHERE JUXTAPOSED WITH AT LEAST MRGL LOW-LEVEL
MOISTURE...CINH WILL BE ERODED FOR WIDELY SCATTERED
TSTMS...DIMINISHING PRECIPITOUSLY IN COVERAGE/INTENSITY AFTER DARK.
BUOYANCY/SHEAR PROFILES APPEAR TOO WEAK FOR ORGANIZED SVR
THREAT...THOUGH WELL-MIXED SUBCLOUD LAYERS OVER PORTIONS SRN GREAT
BASIN/NRN AZ REGION COULD SUPPORT STG GUSTS FROM SOME CELLS.
...SRN PLAINS TO LOWER MS VALLEY...
RIDGING IS FCST TO LINGER ACROSS GULF COAST THROUGH MUCH OF THIS
PERIOD...CHARACTERIZED BY WEAK SFC FLOW AND PRECLUDING ROBUST RETURN
OF BOUNDARY LAYER MOISTURE. HOWEVER...PARTIALLY MODIFIED
RETURN-FLOW AIR MASS...CHARACTERIZED BY SFC DEW POINTS 50S F...MAY
REACH RED RIVER REGION AND SWD-MOVING SFC FRONT BY END OF PERIOD.
DEVELOPMENT OF SFC-BASED CONVECTION INVOF SFC FRONT IS POSSIBLE LATE
AFTERNOON...BUT IN QUESTION BECAUSE OF CAPPING. DURING LATTER HALF
OF PERIOD...PW PLUME WILL BE ENTRAINED INTO ELEVATED WAA/MOIST
ADVECTION REGIME OVER AND N OF SFC COLD FRONT...AND ISENTROPICALLY
HOISTED TO LFC IN SOME PORTIONS OF TSTM OUTLOOK AREA. MUCAPE VALUES
IN 500-1000 J/KG RANGE MAY DEVELOP WITH ACTIVITY MOVING SWD TO SEWD
THROUGH 19/12Z. SVR POTENTIAL APPEARS TOO MRGL/CONDITIONAL TO
ASSIGN PROBABILITIES ATTM...GIVEN WEAK EFFECTIVE SHEAR IN FCST
SOUNDINGS AND LACK OF MORE ROBUST MOISTURE.
..EDWARDS.. 10/17/2010
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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:
Post a Comment