[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 311622
SWODY1
SPC AC 311620

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1120 AM CDT MON JUL 31 2006

VALID 311630Z - 011200Z

...THERE IS A SLGT RISK OF SVR TSTMS UPPER GREAT LAKES AND  UPPER MS
VALLEY...

...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF UPSTATE NY AND WRN
NEW ENGLAND...

...SYNOPSIS...
WARM UPPER RIDGE SHIFTS EWD ACROSS GREAT LAKES AS A VIGOROUS SYSTEM
TRACKS WELL N OF CONUS ACROSS SCENTRAL CANADA. IN THE WESTERN U.S. A
BROAD TROUGH MOVES INTO NRN INTERMOUNTAIN REGION AS WEAK UPPER
CIRCULATION THAT HAS RESIDED OVER THE WEEKEND IN NM BEGINS TO LIFT
SLOWLY NEWD INTO CENTRAL HIGH PLAINS.

COLD FRONT TRAILING SWWD FROM STRONG CANADIAN SYSTEM THRU ERN ND TO
ERN CO WILL PUSH STEADILY EWD TO UPPER GREAT LAKES BY LATER TONIGHT
STRETCHING SWWD ACROSS NEB TO SERN CO.

VERY MOIST AIR MASS BOTH FROM SWLY FLOW AHEAD OF NM UPPER SYSTEM 
AND LARGE AREA OF GULF MOISTURE ALREADY IN PLACE COVERS MUCH OF
REGION FROM COLD FRONT TO APPALACHIANS.

...GREAT LAKES ...
THE VERY WARM MID LEVEL TEMPERATURES SPREADING EWD WITH UPPER RIDGE
WILL LIMIT SEVERE STORM POTENTIAL AHEAD OF COLD FRONT EVEN WITH 
ABUNDANT MOISTURE...INSTABILITY AND A FAVORABLY SHEARED ENVIRONMENT
CURRENTLY IN PLACE ACROSS THE UPPER GREAT LAKES.

OUTFLOW BOUNDARY THAT CURRENTLY EXTENDS WWD FROM CONVECTIVE COMPLEX
NRN LH WOULD BE A FOCUS OF SURFACE BASED THUNDERSTORMS NRN LWR MI
THIS AFTERNOON AS AIR MASS ALREADY VERY UNSTABLE AND WEAKLY CAPPED.
HOWEVER WITH WARMER AIR ALOFT SPREADING EWD SEVERE POTENTIAL SHOULD
DIMINISH BY EVENING.

UPSTREAM OVER MN AND NRN WI STRONG HEATING WILL WEAKEN CAP
SUFFICIENTLY TO ALLOW THUNDERSTORMS TO INITIATE BY MID/LATE
AFTERNOON AS MLCAPES CLIMB TO NEAR 2000 J/KG.  HOWEVER WITH VERY
WARM MID LEVELS...SEVERE THUNDERSTORM POTENTIAL WILL BE LIMITED TO
DOWNBURSTS WITH STEEP LOW LEVEL LAPSE RATES AND ONLY A MARGINAL
SEVERE HAIL THREAT.

...NY/VT...
HAVE CONTINUED A CONDITIONAL LOW END SEVERE THREAT FOR TONIGHT FOR
POTENTIAL OF MCS RIDING ACROSS UPR RIDGE AND TRACKING SEWD INTO NRN
NY AND VT. WHILE DEEP LAYER SHEAR OF 40KT WOULD SUPPORT A SEVERE
THREAT THE INSTABILITY IS CERTAINLY A CONCERN GIVEN THE WARM 500 MB
TEMPERATURES AND LAPSE RATES OF 6C/KM OR LESS. WILL CONTINUE
PRIMARILY A CONDITIONAL WIND DAMAGE THREAT FOR MCS OCCURRENCE AFTER
00Z.

..HALES/GUYER.. 07/31/2006