[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 270051
SWODY1
SPC AC 270049

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0649 PM CST SUN NOV 26 2006

VALID 270100Z - 271200Z

...NO SVR TSTM AREAS FORECAST...

...CENTRAL PLAINS NEWD TO PARTS OF WRN GREAT LAKES...
EARLY EVENING SATELLITE IMAGERY INDICATED A LOW AMPLITUDE SHORT WAVE
TROUGH OVER NEB/NRN KS.  THIS FEATURE WILL PROGRESS NEWD WITHIN SWLY
FLOW ALOFT...REACHING SERN MN/WI BY 12Z MONDAY...AS THE NEXT
UPSTREAM IMPULSE TRACKS NEWD INTO THE SRN HIGH PLAINS. IN THE LOW
LEVELS...AN ARCTIC COLD FRONT WILL CONTINUE TO SPREAD SWD THROUGH
THE CENTRAL PLAINS OVERNIGHT AND SHOULD EXTEND FROM THE NRN TX
PANHANDLE/NW OK REGION NEWD INTO NWRN MO AND CENTRAL IA TO SERN MN
BY END OF DAY 1 PERIOD.  MEANWHILE...A SECOND BOUNDARY MARKING NWD
EXTENT OF LOW LEVEL MOISTURE RETURN /SURFACE DEWPOINTS IN THE LOWER
50S/ SHOULD REMAIN STATIONARY FROM NERN IA THROUGH SRN WI TO CENTRAL
LOWER MI.

STRENGTHENING SWLY LLJ EXTENDING FROM SRN PLAINS TO SRN/ERN IA WILL
MAINTAIN MOISTURE RETURN...WHILE ASCENT WITHIN WAA IN VICINITY OF
LLJ AND DEEP LAYER ASCENT AHEAD OF CENTRAL PLAINS TROUGH EXPECTED TO
SUPPORT INCREASE IN CONVECTION.  ACTIVITY SHOULD SPREAD NEWD ALONG/N
OF STATIONARY BOUNDARY...POTENTIALLY REACHING LM AND WRN LOWER MI AS
UPPER TROUGH APPROACHES WI BY 27/12Z.  PLUME OF STEEP LAPSE RATES
/7.5 TO 8 C/KM PER 27/00Z SOUNDINGS FROM NEB TO WI/ ATOP LOW LEVEL
WARM AIR AND MOISTURE ADVECTION COMBINED WITH EFFECTIVE BULK SHEAR
OF 25-30 KT SUGGEST POTENTIAL FOR MARGINALLY SEVERE HAIL WITH
STRONGER STORMS.  HOWEVER...SEVERE THREAT SHOULD REMAIN TOO LOW...
GIVEN WEAK INSTABILITY...AND THUS PRECLUDE INTRODUCTION OF SEVERE
PROBABILITIES.

SECOND AREA OF INCREASING ISENTROPIC ASCENT...IN ADVANCE OF IMPULSE
APPROACHING SRN HIGH PLAINS...OVER PARTS OF CENTRAL KS AND
POTENTIALLY FAR NW OK TO THE NORTH OF SURGING COLD FRONT SUGGESTS
THREAT FOR TSTMS LATE IN FORECAST PERIOD.

...PACIFIC NW COAST SWD ALONG NRN/CENTRAL CA COAST...
A FEW LIGHTNING STRIKES REMAIN POSSIBLE...MAINLY ALONG AND OFFSHORE
OF THE CENTRAL CA COAST...AS ASCENT WITH A SHORT WAVE TROUGH SPREADS
SEWD ACROSS CENTRAL TO SRN CA. ADDITIONAL TSTMS ARE POSSIBLE
FARTHER N ALONG THE PACIFIC NW COAST AS COLD MID LEVEL TEMPERATURES
/LESS THAN -30 C AT 500 MB/ WITH DEEPENING VORTEX SPREAD INLAND ATOP
MOIST...POST-FRONTAL ONSHORE FLOW.

..PETERS.. 11/27/2006