[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 250105
SWODY1
SPC AC 250103

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0803 PM CDT THU AUG 24 2006

VALID 250100Z - 251200Z

...THERE IS A MDT RISK OF SVR TSTMS FROM SOUTHEAST SOUTH DAKOTA
ACROSS SOUTHERN MINNESOTA AND PARTS OF SOUTHWEST WISCONSIN...

...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK AREA
FROM ERN SD TO LAKE MI SWD TO KS AND WRN MO...

...VOLATILE SEVERE WEATHER SITUATION CONTINUING ACROSS EASTERN SOUTH
DAKOTAS...SOUTHERN MINNESOTA...AND WESTERN WISCONSIN THIS EVENING...


COMPACT AND FAST MOVING MID LEVEL IMPULSE AND ASSOCIATED 50-60KT WLY
SPEED MAX WILL CONTINUE TO DRIVE DANGEROUS SEVERE WEATHER EPISODE
ACROSS PARTS OF THE NRN PLAINS/UPPER MS VALLEY INTO TONIGHT. A PLUME
OF EXTREMELY UNSTABLE AIR /MLCAPE IN EXCESS OF 5000 J PER KG/
CONTINUES TO WRAP INTO THE WARM SECTOR OF ASSOCIATED VIGOROUS
SURFACE CYCLONE MOVING EWD ALONG INTENSE WARM FRONT FROM ERN SD AND
SRN MN. IN ADDITION TO VERY MOIST AND HIGHLY UNSTABLE AIR
MASS...PRONOUNCED DIRECTIONAL SHEAR EXISTS NEAR OUTFLOW-REINFORCED
WARM FRONT OVER SRN MN...WHERE LATEST DIAGNOSTIC DATA INDICATES
0-1KM SRH GREATER THAN 250 M2/S2. THESE CONDITIONS WILL CONTINUE TO
FUEL INTENSE SUPERCELLS WITH TORNADOES...HIGH WINDS...AND VERY LARGE
HAIL OVER PORTIONS OF SERN SD INTO SCNTRL MN THIS EVENING.

ONGOING TORNADIC SUPERCELL WAS RECENTLY MOVING NEAR HURON SD AND
APPEARS TO BE LOCATED IN CLOSE PROXIMITY TO SYNOPTIC SURFACE LOW.
DAMAGING TORNADOES WERE ALSO RECENTLY REPORTED IN NICOLLET AND LE
SEUR COUNTIES IN SCNTRL MN. TORNADIC SUPERCELLS OVER MN APPEAR TO
HAVE FORMED ON THE INTENSE WARM FRONT SOUTH OF MSP. ADDITIONAL
ELEVATED ACTIVITY WAS TRACKING NORTH OF THE WARM FRONT AND WILL
CONTINUE TO PRODUCE HAIL AND LOCALLY STRONG WINDS FROM THE MSP AREA
INTO WRN WI THIS EVENING.

SD SUPERCELL MAY PERSIST WITHIN NARROW CORRIDOR BETWEEN RELATIVELY
STRONG WARM SECTOR CAP ALONG/SOUTH OF THE SD/MN BORDERS...AND
OUTFLOW AIR MASS NORTH OF THE WARM FRONT. HOWEVER...LATEST GUIDANCE
APPEARS TO SUGGEST THAT CAP...TIME OF DAY...AND DEAMPLIFICATION OF
UPPER WAVE...MAY BEGIN TO TEMPER SEVERE WEATHER POTENTIAL FROM SWRN
MN INTO IA OVERNIGHT. DESPITE THESE INDICATIONS...LIFT ALONG THE
COLD FRONT/WIND SHIFT WILL DEVELOP SEWD INTO THE INSTABILITY AXIS
ACROSS THESE AREAS LATER TONIGHT. THIS WARRANTS MAINTAINING A SLGT
RISK AND RELATIVELY LOW SEVERE PROBABILITIES OVER THE AREA AT THIS
TIME.

...NEB/ERN KS/WRN MO...
HOT AND MODERATELY UNSTABLE AIR MASS SHOULD PERSIST ACROSS THE CNTRL
PLAINS AS FRONT/WIND SHIFT SPREADS SEWD OVERNIGHT. LATEST NAM-WRF
AND NCEP-SREF WERE INDICATING A POTENTIAL FOR SCATTERED TSTM
DEVELOPMENT AS THE FRONT MOVES SEWD. SHEAR ACROSS THE AREA APPEARS
MARGINALLY SUPPORTIVE OF UPDRAFT PERSISTENCE AND IF A CLUSTER OR TWO
OF STORMS CAN DEVELOP...MASS INFLOW ON THE PLAINS NOCTURNAL LOW
LEVEL JET MAY BE ENOUGH TO SUSTAIN STORMS INTO EARLY FRIDAY FROM
SERN KS INTO WRN MO. PROBABILITY OF HAIL AND HIGH WINDS WITH THIS
POTENTIAL ACTIVITY APPEARS GREAT ENOUGH TO WARRANT  A SLGT RISK
ACROSS THE MO RIVER VALLEY FOR THE REST OF TONIGHT.

..CARBIN.. 08/25/2006