[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 050039
SWODY1
SPC AC 050038

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0738 PM CDT MON SEP 04 2006

VALID 050100Z - 051200Z

...NO SVR TSTM AREAS FORECAST...

...ERN IA INTO NRN IL/SRN WI...

AN ARCING CLUSTER OF TSTMS CONTINUES THIS EVENING AHEAD OF UPPER LOW
FROM NEAR ORD SSWWD TO E OF DEC ALONG LOW-LEVEL BAROCLINIC ZONE. 
THIS ACTIVITY HAS TENDED TO WEAKEN OVER THE PAST 1-2 HOURS...AND
SHOULD CONTINUE TO DO SO THROUGH THE REMAINDER OF THE EVENING AS
BOUNDARY LAYER COOLS AND STABILIZES.  DEEP LAYER FORCING FOR ASCENT
AHEAD UPPER LOW COUPLED WITH EXISTING WEAK INSTABILITY /REF. 00Z ILX
SOUNDING/ MAY SUPPORT A FEW STRONG STORMS THROUGH 02Z WITH THE
PRIMARY THREAT BEING MARGINALLY SEVERE HAIL.

...CNTRL APPALACHIANS...

A SMALL CLUSTER OF TSTMS HAS RECENTLY DEVELOPED OVER SERN TN / ENE
OF CHA/ INVOF OF WEAK SURFACE LOW SITUATED ALONG SURFACE BOUNDARY
EXTENDING FROM SERN MS TO NRN GA AND THEN ENEWD THROUGH CNTRL NC.
OTHER STORMS ARE ALSO INTENSIFYING OVER CNTRL NC WITHIN A MOIST
LOW-LEVEL AIR MASS WITH MUCAPES OF 500-1000 J/KG.  WATER VAPOR
IMAGERY SHOWS A FAIRLY STRONG SHORT WAVE TROUGH TRANSLATING EWD
THROUGH THE TN AND SRN OH VALLEY...WHICH SHOULD SUPPORT AN INCREASE
IN CONVECTIVE COVERAGE ACROSS THE CNTRL APPALACHIANS THIS EVENING.

DESPITE THE MODEST INSTABILITY...BNA VWP INDICATES THE PRESENCE OF A
50 KT MID-LEVEL JET STREAK WHICH WILL SHIFT EWD ACROSS REGION
TONIGHT...EFFECTIVELY ENHANCING VERTICAL SHEAR.  THE MAJORITY OF
TSTM ACTIVITY IS EXPECTED TO REMAIN SUB-SEVERE...HOWEVER THE
INCREASING VERTICAL SHEAR MAY SUPPORT A FEW ORGANIZED STORMS CAPABLE
OF MAINLY LOCALLY DAMAGING WINDS.

...WRN AZ INTO SERN CA...

AN INTENSE CLUSTER OF TSTMS HAS RECENTLY DEVELOPED OVER SRN MOHAVE
COUNTY WITHIN A HOT AND DEEPLY MIXED BOUNDARY LAYER WITH SBCAPES OF
1000-1500 J/KG.  POTENTIAL WILL EXIST FOR THESE STORMS TO FORM A
COLD POOL AND PROPAGATE SWWD ALONG THE CO RIVER VALLEY WHERE
TEMPERATURES REMAIN 95-105 F.  STRONG EVAPORATIONAL COOLING
POTENTIAL IN THE SUB-CLOUD LAYER WILL BE SUPPORTIVE OF LOCALLY
DAMAGING WINDS THROUGH THE REMAINDER OF THE EVENING.

..MEAD.. 09/05/2006