[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 280559
SWODY1
SPC AC 280557

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1157 PM CST MON DEC 27 2004

VALID 281200Z - 291200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 15 WSW EKA 45 ENE UKI
20 SSE SCK 50 SSE FAT 25 E NID 40 NW IGM 20 NNE FLG 25 S INW 55 WNW
SAD 25 SW FHU.

...NO SVR TSTM AREAS FORECAST...

...SYNOPSIS...
MODELS TEND TO AGREE IN THE EVOLUTION OF THE OVERALL UPPER PATTERN
FOR THE DAY 1 PERIOD WITH THE CLOSED UPPER LOW OFF THE WEST COAST
DE-AMPLIFYING TODAY AND THEN MOVING INLAND TONIGHT AS AN OPEN WAVE. 
THIS OCCURS AS AN UPSTREAM TROUGH OVER THE GULF OF AK DIGS SEWD
TOWARD THE PAC NW/NRN CA REGION.  HOWEVER...ETA/GFS/ECMWF DIFFER IN
THE STRENGTH OF THE UPPER TROUGH AS IT MOVES INLAND TONIGHT AND THE
MOVEMENT OF THE SURFACE LOW.  THE GFS IS DEEPER WITH THE UPPER
TROUGH AND FASTER WITH THE SURFACE LOW WHICH IS EXPECTED TO BE OVER
EAST CENTRAL CA BY THE END OF PERIOD.  THE SLOWER ETA/ECMWF PLACE
THE SURFACE LOW JUST OFFSHORE OF POINT CONCEPTION BY 12Z WEDNESDAY.

...SRN CA...
DESPITE THESE MODEL DIFFERENCES...THERE IS AGREEMENT THAT ONE SHORT
WAVE TROUGH /CURRENTLY LOCATED AT 30.5N/127.7W PER SATELLITE
IMAGERY/ WILL MOVE INLAND ACROSS SRN CA BY LATE THIS MORNING...WITH
A SECOND SHORT WAVE TROUGH REACHING SRN CA BY 12Z WEDNESDAY. 
CURRENT OCEANIC LIGHTNING DATA SHOWED NUMEROUS STRIKES WITH THE LEAD
SHORT WAVE TROUGH.

EXTENSIVE AREA OF CLOUDS WITH ONGOING PRECIPITATION WILL BE OVER SRN
CA AT THE START OF THE PERIOD...GIVEN STRONG LARGE SCALE ASCENT OVER
THIS AREA AHEAD OF THE LEAD SHORT WAVE TROUGH. THESE CLOUDS/
PRECIPITATION ARE EXPECTED TO MINIMIZE AIR MASS DESTABILIZATION
INLAND...WHILE THE STRONGEST INSTABILITY SHOULD REMAIN JUST OFFSHORE
AS A COLD POOL STEEPENS LAPSE RATES BY LATE MORNING.  THUS...GIVEN
STRONG DEEP LAYER SHEAR...ANY SEVERE THREAT SHOULD REMAIN OFFSHORE.
A GREATER POTENTIAL...ALTHOUGH ALSO SMALL..FOR SEVERE STORMS TO MOVE
INLAND ALONG THE SRN CA COAST WILL BE TONIGHT AS THE MAIN STRONGER
UPPER TROUGH APPROACHES THIS AREA.  NONETHELESS...AS LOW-LEVEL WINDS
BACK IN ADVANCE OF EACH UPPER TROUGH...LOW-LEVEL SHEAR WILL INCREASE
SUPPORTING A THREAT FOR ISOLATED WATERSPOUTS OFF THE COAST OF SRN
CA.

ELSEWHERE...AS PLUME OF STEEP LAPSE RATES AND LARGE SCALE ASCENT
SPREADS FARTHER INLAND TOWARD THE FOUR CORNERS REGION AHEAD OF THE
MID-LEVEL TROUGH...THE POTENTIAL FOR THUNDERSTORMS IS EXPECTED TO
DEVELOP EWD INTO AZ.

..PETERS.. 12/28/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.