[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 041300
SWODY1
SPC AC 041258

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0758 AM CDT FRI AUG 04 2006

VALID 041300Z - 051200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE NRN PLNS/UPR
MS VLY...

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE MID AND S
ATLANTIC CST...

...SYNOPSIS...
SUBTROPICAL RIDGE WILL RETROGRADE SLIGHTLY THIS PERIOD AS LOW
AMPLITUDE IMPULSE CONTINUES E TO THE CANADIAN MARITIMES.  FARTHER N
AND W...STRONGER DISTURBANCES NOW OVER BC EXPECTED TO PHASE OVER THE
CANADIAN RCKYS LATER TODAY...BEFORE CONTINUING E AS A FAIRLY POTENT
SHORTWAVE TROUGH INTO CNTRL/SRN SASKATCHEWAN.

TRAILING FRONT WITH ERN SYSTEM WILL SETTLE SE ACROSS THE MID
ATLANTIC AND TN VLY TODAY...WHILE DOWNSTREAM FROM THE BC/AB
DISTURBANCE...EXPECT LEE LOW AND ASSOCIATED FRONTAL SYSTEM TO
INTENSIFY OVER THE NRN PLNS.

...NRN PLNS...
WEAK IMPULSE PRECEDING BC/AB DISTURBANCE WILL ENHANCE WARM
ADVECTION/JET ENTRANCE REGION ASCENT OVER NRN/ERN ND AND NRN MN
TODAY. BOUNDARY LAYER MOISTURE OVER REGION WILL REMAIN LIMITED. 
BUT COUPLED WITH MID LEVEL STEEP LAPSE RATES AND MODERATE/
UNIDIRECTIONAL CLOUD LAYER WLY FLOW...SETUP SHOULD SUPPORT A
PERSISTENT AREA OF ELEVATED STORMS/POSSIBLE WEAK SUPERCELLS WITH
MARGINALLY SEVERE HAIL.  AS THE BOUNDARY LAYER WARMS AND LOW LEVEL
LAPSE RATES STEEPEN...THIS ACTIVITY COULD ALSO YIELD LOCALLY
DAMAGING WIND. SOME OF THE STORMS COULD SPREAD E TO WRN LK SUPERIOR
EARLY SATURDAY.

FARTHER S...EML SHOULD KEEP DEVELOPING WARM SECTOR CAPPED UNTIL LATE
IN THE DAY.  BUT CONVERGENCE ALONG LEE TROUGH COULD PROMOTE
DEVELOPMENT OF WIDELY SCATTERED HIGH-BASED STORMS FROM CNTRL ND SSW
INTO NW NEB LATE THIS AFTERNOON...WHERE THERMODYNAMIC ENVIRONMENT
COULD SUPPORT A FEW MICROBURSTS.

...SRN DELMARVA SW INTO GA/TN VLY...
HEATING OF VERY MOIST AIR IN PLACE INVOF WEAKENING COLD FRONT AND
LEE TROUGH FROM THE SRN DELMARVA REGION INTO GA WILL BOOST MUCAPE TO
AOA 2500 J/KG. EFFECTIVE DEEP WLY SHEAR WILL BE RATHER WEAK
...RANGING FROM 20-25 KTS IN NRN PART OF SLIGHT AREA TO LESS THAN 10
KTS IN SC.  SLIGHTLY STRONGER ELY SHEAR WILL EXIST FARTHER S ACROSS
SRN GA AND N FL...ON N SIDE OF W-MOVING UPR DISTURBANCE.  WITH
RESIDUAL UPR LEVEL DEFORMATION AXIS AND TERRAIN-INDUCED CIRCULATIONS
TO FOSTER STORM INITIATION...SETUP SHOULD SUPPORT NUMEROUS AFTERNOON
PULSE/MULTICELL STORMS.  STEEP THETA-E LAPSE RATES AND HIGH DCAPE
WILL PROMOTE WET DOWNBURST POTENTIAL.  MORE ISOLATED WET MICROBURST
ACTIVITY COULD OCCUR WWD ALONG TRAILING FRONT INTO THE TN VLY.

...SRN/ERN ID...
SATELLITE LOOPS SHOW AN UPR IMPULSE LIFTING N ACROSS ERN NV
ATTM...DOWNSTREAM FROM OFFSHORE LOW.  INCREASING MID LEVEL MOISTURE
AND UPR LEVEL DIVERGENCE IN ASSOCIATED DEFORMATION ZONE WILL REACH
SRN/ERN ID AFTER MAX HEATING TIME TODAY...WHERE ENVIRONMENT COULD
SUPPORT A SMALL CLUSTER OR TWO OF STORMS WITH LOCALLY DAMAGING WIND.

...SOUTHWEST...
A FEW WET DOWNBURSTS MAY ALSO OCCUR OVER PARTS OF THE SOUTHWEST AS
SUBTROPICAL IMPULSE ENHANCES TSTM COVERAGE OVER REGION. BUT WARM
THERMODYNAMIC PROFILES AND VERY WEAK SHEAR SUGGEST THAT MAIN THREAT
WILL BE LOCALLY HEAVY RAIN.

..CORFIDI/JEWELL.. 08/04/2006