ZCZC SPCSWODY1 ALL
ACUS01 KWNS 282002
SPC AC 282000

STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK 
DAY 1 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWE46 KWNS.

VALID 282000Z - 291200Z

THERE IS A MDT RISK OF SVR TSTMS ACROSS EXTREME ERN SD...SRN/CNTRL
MN AND PARTS OF CNTRL/NRN WI TO THE RIGHT OF A LINE FROM
40 N MSN 50 SSE RST 25 NE YKN 15 SE ATY 55 NNE MSP 30 SE RHI
20 NNW GRB 40 N MSN.

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM
15 NNE ART 25 N PHL 30 ESE BWI 25 NE MGW 20 N ZZV 20 S STL
45 N JLN 45 N EHA 10 E GLD 25 NNW MHN 55 W AXN 60 ENE CMX
40 NE MKG 10 NNW MTC.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 80 NNW 3B1 EPM.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 ESE CRP 30 SW CLL
GGG PBF 50 SSW JBR 65 SSW UNO FSM ADM BWD 60 NW LRD ...CONT...
45 WSW FHU 45 NNE PHX 35 SW FMN 35 WNW FCL 35 E 81V 50 S GDV
40 NW HVR.



...ERN SD/NERN NEB NEWD INTO UPPER MS VLY...
MIDLEVEL SHORTWAVE TROUGH AXIS CONTINUES TO MOVE EWD ACROSS THE
DAKS AND WRN NEB.  LARGE SCALE ASCENT EAST OF THE TROUGH AXIS AND
UNSTABLE ENVIRONMENT HAS SET THE STAGE FOR AN ACTIVE LATE
AFTERNOON/OVERNIGHT PERIOD FOR PARTS OF THE UPPER MS VLY AND CNTRL
PLAINS.

VSBL IMAGERY SHOWS THAT AMPLE SUNSHINE HAS OCCURRED AHEAD OF VERY
LARGE AND INTENSE SEVERE TSTMS OVER ERN SD WITH A WARM FRONT
LIFTING NWD THROUGH SRN MN.  TSTMS SHOULD CONTINUE TO DEVELOP OVER
ERN SD/NERN NEB AND TRACK ENEWD INTO NWRN IA AND SRN/CNTRL MN THIS
EVENING.  VERY UNSTABLE AIR MASS IN PLACE AND DEEP LAYER SHEAR OF
40-45 KTS WILL SUPPORT SUPERCELLS INITIALLY THROUGH EARLY EVENING
ACROSS ERN SD INTO SRN/CNTRL MN.  LOCALLY BACKED WINDS INVOF OF
WARM FRONT OVER SRN MN/EXTREME BUOYANCY MAY AUGMENT LOW LEVEL SRH
TO KEEP A RISK OF TORNADOES FOR A FEW MORE HOURS ALONG WITH VERY
LARGE HAIL.  HOWEVER...ACTIVITY SHOULD CONGEAL INTO A FORWARD
PROPAGATING MCS AND MOVE ENEWD INTO CNTRL/SRN MN...NRN/CNTRL
WI...AND PERHAPS PARTS OF UPPER MI/LAKE MI OVERNIGHT.  GIVEN VERY
UNSTABLE AIR MASS IN PLACE AND MAGNITUDE OF DEEP LAYER WLY
FLOW...POTENTIAL EXIST FOR SIGNIFICANT WIND DAMAGE ACROSS THE
MODERATE RISK AREA.   

...CNTRL PLAINS...
BANDS OF TSTMS CONTINUE TO FORM ALONG LEE TROUGH AND ALONG SRN
PERIPHERY OF MIDLEVEL SHORTWAVE TROUGH ACROSS PARTS OF CNTRL/ERN
NEB AND WRN KS.  HOT BOUNDARY LAYER TEMPERATURES/LARGE DEW POINT
DEPRESSIONS MAY AID IN LOCALLY DAMAGING WIND GUSTS AND PERHAPS HAIL
THROUGH THIS EVENING.  ONE OR TWO CLUSTERS OF TSTMS MAY TRACK ENEWD
ACROSS NRN/CNTRL KS/SRN NEB DURING THE EVENING.

...LOWER GREAT LAKES INTO UPPER OH VLY...
MANY OUTFLOW/LAKE INDUCED BOUNDARIES EXIST FROM NRN IND/SRN MI INTO
NRN OH AND PA/SRN NY.  THIS REGION RESIDES BENEATH ENTRANCE REGION
OF ULJ ACROSS THE LOWER GREAT LAKES AND GIVEN VERY UNSTABLE
CONDITIONS...TSTMS ARE EXPECTED TO CONTINUE DEVELOPING ALONG THESE
BOUNDARIES.  STRONGEST STORMS ARE APT TO ORGANIZE FROM SRN ONTARIO
AND NERN OH AND MOVE ESEWD ACROSS WRN NY AND NRN/CNTRL PA THIS
EVENING.  DEEP LAYER SHEAR IS MORE THAN ENOUGH FOR SUPERCELLS WITH
LARGE HAIL AND DAMAGING WINDS.  HOWEVER...ISOLD TORNADOES ARE ALSO
POSSIBLE OVER NERN OH INTO NRN PA...AS EVIDENCED BY THE APPARENT
LONG TRACK TORNADO THAT OCCURRED NE OF DETROIT INTO SWRN ONTARIO
EARLY THIS AFTERNOON.  ACTIVITY SHOULD BEGIN TO WEAKEN AS IT MOVES
INTO CNTRL/NERN PA LATER THIS EVENING/OVERNIGHT.

...ERN KS INTO NRN MO AND SRN IA...
BOUNDARY LAYER HAS HEATED CONSIDERABLY ACROSS ERN KS INTO NRN MO
AHEAD OF WEAK MIDLEVEL CYCLONIC CIRCULATION LOCATED OVER CNTRL KS. 
SURFACE BASED CU ARE FORMING ALONG REMNANT OUTFLOW BOUNDARY ACROSS
NRN MO.  PRIND THAT TSTMS WILL FORM ACROSS NRN KS INTO NRN MO AND
MOVE ENEWD INTO SRN IA DURING THE EVENING.  VERTICAL SHEAR DERIVED
FROM REGIONAL PROFILERS IS NOT PARTICULARLY STRONG...BUT GIVEN
TEMPERATURES IN THE 90S AND HIGH PRECIPITABLE WATER
VALUES...DAMAGING WIND GUSTS AND PERHAPS HAIL WILL OCCUR WITH THE
STRONGER STORMS.  ACTIVITY WILL LIKELY TRANSLATE ENEWD INTO
NRN/CNTRL IL BY MORNING WITH ISOLD DAMAGING WINDS THE MAIN THREAT.

...SRN PLAINS...
VSBL MOVIE LOOPS INDICATE SEVERAL VORT CENTERS MOVING NEWD WITHIN
ELEVATED MIDLEVEL CONVECTION FROM THE S PLAINS OF W TX INTO OK.  AS
SWLY LLJ INCREASES THIS EVENING...TSTMS ARE EXPECTED TO BECOME MORE
NUMEROUS AND PERHAPS PRODUCE AN ISOLD DAMAGING WIND GUST OR HAIL. 
BY MORNING...ONE OR TWO TSTM CLUSTERS COULD BE ONGOING SOMEWHERE
OVER NRN OK INTO SWRN MO. 
 
..RACY.. 07/28/02
NNNN