[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 210527
SWODY1
SPC AC 210525

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1125 PM CST MON NOV 20 2006

VALID 211200Z - 221200Z

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...

INTENSE MID AND UPPER LOW EVOLVING OVER SRN GA/FL PNHDL INTO THE
NERN GULF OF MEXICO WILL CONSTRICT SLIGHTLY AS IT SLOWLY SHIFTS EWD
OFF THE FL ATLANTIC COAST.  IN THE W...A BROAD BELT OF CYCLONIC FLOW
WILL EXIST IN THE MID LEVELS FROM THE ERN PACIFIC INTO THE NRN
ROCKIES.  SHORT WAVE TROUGH EMBEDDED WITHIN THIS REGIME NOW
APPROACHING THE WA/ORE COAST WILL TRANSLATE EWD INTO THE NRN ROCKIES
BY TONIGHT WHILE NEXT UPSTREAM IMPULSE DIGS SEWD FROM THE GULF OF AK
TO OFF THE PACIFIC NW COAST BY WEDNESDAY MORNING.

IN THE LOW-LEVELS...SURFACE LOW ATTENDANT TO FL UPPER LOW WILL
REMAIN QUASI-STATIONARY OVER THE GULF STREAM WHILE GRADUALLY
UNDERGOING OCCLUSION.  WELL TO THE NW...LEE CYCLONE IS FORECAST TO
INTENSIFY OVER ALBERTA INTO SASKATCHEWAN IN RESPONSE TO APPROACH OF
LEAD SHORT WAVE TROUGH THROUGH THE NRN ROCKIES.  LOW-LEVEL ONSHORE
FLOW WILL CONCURRENTLY INCREASE ALONG THE PACIFIC NW COAST...IN WAKE
OF BAROCLINIC ZONE INTENSIFYING FROM THE LOW OVER THE CANADIAN HIGH
PLAINS SWWD INTO ERN ORE.

...SRN ATLANTIC COAST...

LOW-LEVEL BAROCLINIC ZONE N AND NW OF SURFACE LOW IS EXPECTED TO
REMAIN OVER THE SHELF WATERS WITH RESPONSE TO FRONTOGENESIS AND
LOW-LEVEL WAA MAINTAINING ISOLATED/SCATTERED STORMS ALONG THIS
BOUNDARY.  FORECAST SOUNDINGS SUGGEST THAT ANY STORMS DEVELOPING
ALONG THE IMMEDIATE COAST WILL LIKELY REMAIN ELEVATED AND BASED
AROUND 850 MB WITHIN WEAKLY UNSTABLE ENVIRONMENT WITH MUCAPES OF
AROUND 100 J/KG.

...NRN ROCKIES...

INCREASED HEIGHT FALLS ASSOCIATED WITH SHORT WAVE TROUGH MOVING
THROUGH WA/ORE ARE EXPECTED TO CONTRIBUTE TO STEEPENING LAPSE RATES
AND DEVELOPMENT OF WEAK CONVECTIVE INSTABILITY LATER TODAY INTO
TONIGHT.  ISOLATED TSTMS EMBEDDED IN SHALLOWER CONVECTION WILL
BECOME INCREASINGLY LIKELY AT THIS TIME ALONG STRENGTHENING LOW
LEVEL BAROCLINIC ZONE THAT WILL STRETCH FROM WRN MT INTO ERN ORE.

...PACIFIC NW COAST...

MOIST ONSHORE FLOW IN THE LOW LEVELS BENEATH COLD MID LEVEL
TEMPERATURES OF AROUND -30 C AT 500 MB WILL RESULT IN RATHER STEEP
LAPSE RATES AND WEAK CONVECTIVE INSTABILITY.  IT APPEARS THE BEST
POTENTIAL FOR ISOLATED TSTM ACTIVITY WILL EXIST THIS MORNING IN
ASSOCIATION WITH LEAD SHORT WAVE TROUGH...AND TOWARD THE END OF THE
PERIOD WEDNESDAY MORNING AS NEXT UPSTREAM SYSTEM APPROACHES FROM THE
W.

..MEAD/BOTHWELL.. 11/21/2006