SPC AC 101919
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0119 PM CST WED NOV 10 2010
VALID 102000Z - 111200Z
...NO SVR TSTM AREAS FORECAST...
...UPPER MS VALLEY...
HAVE OPTED TO REMOVE SEVERE PROBS ACROSS THE UPPER MS VALLEY AS THE
THREAT FOR DAMAGING WINDS APPEARS TOO LOW TO WARRANT A MEANINGFUL
RISK AT THIS TIME.
NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS HAVE DEVELOPED WITHIN
STRONGER FORCING BOTH ALONG AND BEHIND THE ADVANCING FRONTAL ZONE
FROM SERN SD...NWD INTO WCNTRL MN. THIS ACTIVITY HAS EVOLVED WITHIN
A THICK CLOUD CANOPY ATOP AN EXPANDING LOW LEVEL STRATUS DECK. AS A
RESULT...LOW LEVEL LAPSE RATES ARE NOT PARTICULARLY STEEP ALONG THE
FRONT ACROSS MN AND MEAGER MOISTURE IS YIELDING MUCAPE VALUES NO
MORE THAN 100-200 J/KG. AT THIS TIME IT APPEARS THERMODYNAMIC
PROFILES ARE JUST TOO WEAK TO WARRANT A SEVERE THREAT.
..DARROW.. 11/10/2010
.PREV DISCUSSION... /ISSUED 0956 AM CST WED NOV 10 2010/
IA/MN
PRIMARY SURFACE LOW SRN MAN/ND BORDER WITH COLD FRONT SWD ALONG WRN
MN BORDER TO A WEAK WAVE OVER SERN NEB THIS AM. WHILE AIR MASS
AHEAD OF FRONT THIS AREA IS INITIALLY LACKING IN MOISTURE AND
INSTABILITY...THE ABSENCE OF CLOUDINESS WILL LEAD TO GOOD DAYTIME
HEATING AND STEEPENING LOW/MID LEVEL LAPSE RATES FROM ERN IA INTO
SRN MN.
LOW CLOUDS ARE RACING NWD THRU ERN KS/WRN MO THIS AM AS DEWPOINTS
RISE INTO THE MID 50S. THIS MOISTURE WILL MOVE THRU IA E OF COLD
FRONT INTO SRN MN DURING THE AFTERNOON WHICH COUPLED WITH THE
STEEPENING LAPSE RATES WILL LEAD TO VERY MARGINAL INSTABILITY IN
SUPPORT OF CONVECTION...MLCAPES GENERALLY NO HIGHER THAN ABOUT 200
J/KG.
WITH THE WAVE ON SURFACE FRONT SERN NE MOVING NNEWD THRU WRN MN THIS
AFTERNOON AS THE STRONG UPPER TROUGH NOW CENTRAL PLAINS ROTATES NWD
INTO UPR MS VALLEY...THE COLD FRONT SHOULD PICK UP SPEED AS IT
CROSSES MN/IA THIS AFTERNOON/EVENING.
DEEP UVV WITH CNTRL PLNS TROUGH...AND LOW LVL UPLIFT ALONG
ASSOCIATED COLD FRONT...SHOULD SUPPORT A BAND OR TWO OF SCTD
SHOWERS/TSTMS ALONG AND JUST AHEAD OF FRONT OVER PARTS OF IA AND MN
LATE TODAY/EARLY TONIGHT.
WITH THE MINIMAL INSTABILITY AND LARGELY UNIDIRECTIONAL LOW TO MID
LVL WIND FIELD THE ONLY THREAT EXPECTED TO BE MARGINALLY SVR WIND
GUSTS.
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
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