[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 040059
SWODY1
SPC AC 040057

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0757 PM CDT MON JUL 03 2006

VALID 040100Z - 041200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE GREAT LAKES/MIDWEST
INTO OH VALLEY...

...SYNOPSIS...
CLOSED UPPER LOW WILL CONTINUE TO MOVE ESEWD ACROSS NRN ONTARIO WITH
30-40 METER HEIGHT FALLS EXPECTED OVER THE GREAT LAKES/OH VALLEY
REGION OVERNIGHT.  BROAD CYCLONIC FLOW REGIME WILL BE MAINTAINED
FROM THE UPPER MS VALLEY THROUGH THE GREAT LAKES/OH VALLEY TO NERN
STATES.  STRONGER WLY MID LEVEL WINDS /40 KT/ AND STRENGTHENING
WSWLY LLJ /35-40 KT/ EXPECTED FROM THE MIDWEST THROUGH THE OH
VALLEY.

...GREAT LAKES/MIDWEST INTO OH VALLEY...
EARLY EVENING SURFACE ANALYSIS SHOWED A WAVY STATIONARY BOUNDARY
EXTENDING FROM OH WNWWD TO NRN IL...AND THEN SWWD INTO SERN IA TO
SWRN KS.  A COLD FRONT EXTENDING FROM THE ERN U.P. OF MI SWWD
THROUGH CENTRAL WI TO NRN IA AND GENERALLY BISECTING NEB FROM NE-SW
WILL CONTINUE TO ADVANCE ESE OVERNIGHT AND SHOULD REACH A LINE FROM
SRN LOWER MI TO THE IA/MO BORDER BY 12Z TUESDAY.  CURRENT OBJECTIVE
ANALYSIS INDICATED A VERY UNSTABLE AIR MASS ACROSS ERN IA/SRN WI/NRN
IL...WITH MUCH OF THE AIR MASS AHEAD OF THE COLD FRONT AND ALONG THE
STATIONARY BOUNDARY EXPECTED TO REMAIN MODERATELY UNSTABLE THROUGH
06Z.  INCREASING WNWLY MID LEVEL WINDS WILL MAINTAIN STRONG
EFFECTIVE BULK SHEAR VALUES THIS EVENING/OVERNIGHT SUPPORTING
ADDITIONAL ORGANIZED STRONG TO SEVERE STORMS ALONG THE PROGRESSIVE
COLD FRONT WITH HAIL/STRONG WIND GUSTS THE PRIMARY THREATS.

WATER VAPOR IMAGERY INDICATED SEVERAL EMBEDDED IMPULSES TRANSLATING
EWD FROM THE LOWER MO VALLEY/MIDWEST THROUGH THE OH VALLEY WITH ONE
SUCH FEATURE CURRENTLY LOCATED OVER SRN WI/NRN IL.  ASCENT AHEAD OF
THIS IMPULSE COMBINED WITH DESTABILIZATION/LOW LEVEL ASCENT ALONG A
STRENGTHENING SWLY LLJ OVER IL/IND THIS EVENING SHOULD AID IN AN
INCREASE IN THUNDERSTORMS ALONG THE STATIONARY BOUNDARY.  THIS TREND
IS CURRENTLY INDICATED BY REGIONAL RADARS FROM CENTRAL IL INTO NWRN
IND WITH STRONG WIND GUSTS/HAIL AND AN ISOLATED TORNADO THREAT
POSSIBLE.  THIS LLJ SHOULD VEER TO WLY OVERNIGHT AS IT TRANSLATES
EWD INTO THE CENTRAL/UPPER OH VALLEY SUPPORTING A CONTINUED THREAT
FOR DAMAGING WINDS EWD INTO OH.

...NRN/CENTRAL HIGH PLAINS...
SHORT WAVE TROUGH...CURRENTLY LOCATED OVER CENTRAL MT/NRN WY WILL
CONTINUE TO ADVANCE EWD REACHING THE WRN DAKOTAS BY 12Z TUESDAY. 
ASCENT AHEAD OF THIS FEATURE COMBINED WITH PROGGED INCREASE IN
UPSLOPE FLOW INTO SERN MT/ERN WY OVERNIGHT SUGGEST SCATTERED
THUNDERSTORMS SHOULD PERSIST AT LEAST THROUGH THE EVENING. 
EFFECTIVE BULK SHEAR VALUES WILL REMAIN SUFFICIENT FOR ORGANIZED
STORMS...BUT WEAK INSTABILITY SHOULD CONTINUE TO LIMIT THE OVERALL
SEVERE COVERAGE.

..PETERS.. 07/04/2006