[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 182005
SWODY1
SPC AC 182003

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0203 PM CST SUN DEC 18 2005

VALID 182000Z - 191200Z

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 30 NW OTH 40 NW MFR
20 SSE MFR 35 SE MHS 45 W RNO 50 SSW TVL 25 N MER 45 WNW MRY.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 35 WSW PIE 40 ESE
DAB.

...NO SVR TSTM AREAS FORECAST...

...PARTS OF CENTRAL/NRN CA TO SWRN ORE...
WV IMAGERY INDICATED A MID LEVEL CLOSED LOW/TROUGH LOCATED OFF THE
COAST OF NWRN CA/SWRN ORE...WITH AN EMBEDDED SHORT WAVE TROUGH OVER
THE SFO AREA.  BOTH OF THESE MID LEVEL FEATURES WILL CONTINUE TO
MOVE INLAND THIS FORECAST PERIOD...WITH FURTHER WEAKENING EXPECTED
AS THEY MOVE INTO THE WRN U.S. RIDGE.  EXTENSIVE CLOUDINESS ACROSS
INLAND CENTRAL/NRN CA TO ORE HAS LIMITED THE DEVELOPMENT OF STRONGER
INSTABILITY INLAND...WITH THE GREATEST SBCAPE VALUES /100-500 J/KG/
LOCATED ALONG COASTAL REGIONS FROM AROUND SFO-EKA.  17Z RUC FORECAST
SOUNDINGS INDICATED A STABLE BOUNDARY LAYER /LOWEST 1 KM/ INDICATIVE
OF THE LACK OF DESTABILIZATION DUE TO THE CLOUDINESS.

REGIONAL RADARS HAVE SHOWN A COUPLE OF STORMS FROM THE AREAS AROUND
SFO TO SAC WITH LOW LEVEL SHEAR COUPLETS.  RUC FORECAST SOUNDINGS
AND AREA VADS INDICATED SUFFICIENT DIRECTIONAL AND SPEED SHEAR ABOVE
THE STABLE BOUNDARY LAYER TO SUPPORT THESE SHEAR COUPLETS. 
ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON INTO THE
EARLY EVENING ACROSS THE SFO-SAC AREA AND NWD TO SWRN ORE AS STEEP
LAPSE RATES ABOVE THE STABLE BOUNDARY LAYER PROVIDE ENOUGH
INSTABILITY FOR CONVECTION.  HOWEVER...THE WEAK BOUNDARY LAYER LAPSE
RATES SHOULD FURTHER PRECLUDE STRONGER WINDS AND/OR STORM ROTATIONS
FROM REACHING THE SURFACE.  IF ANY POCKETS OF SURFACE HEATING CAN
DEVELOP ALLOWING FOR STRONGER SBCAPE...THEN A FEW SEVERE STORMS
WOULD BE POSSIBLE GIVEN THE STRONG DEEP LAYER AND LOW LEVEL SHEAR
VALUES OVER THIS REGION.  THUS...HAVE ADDED LOW TORNADO AND WIND
PROBABILITIES TO PARTS OF THE CENTRAL/NRN CA.

...SRN FL...
DESPITE LACK OF THUNDERSTORMS ACROSS SRN FL AT THIS TIME...
INSTABILITY ALONG/S OF SURFACE FRONT IS SUFFICIENT TO SUPPORT
SCATTERED THUNDERSTORM DEVELOPMENT.  THUS...WILL MAINTAIN GENERAL
THREAT FOR THUNDERSTORMS.

..PETERS.. 12/18/2005

...NOTICE...
THE STATION RELATIVE POINTS IN THIS PRODUCT WILL BE
DISCONTINUED ON 14 FEBRUARY 2006 BUT WILL REMAIN AVAILABLE
IN THE FOLLOWING PRODUCTS:

   WMO HEADER:       AWIPS ID:
   WUUS01            PTSDY1
   WUUS02            PTSDY2
   WUUS03            PTSDY3

A SERVICE CHANGE NOTICE ...SCN05-39... PROVIDES DETAILS
ON THE TRANSITION. FOR ADDITIONAL DETAILS SEE THE FOLLOWING
WEB ADDRESS USING LOWER CASE LETTERS:
WWW.NWS.NOAA.GOV/OM/NOTIF.HTM