High Surf Advisory 13, NWS San Francisco Bay Area, CA

000 
WHUS46 KMTR 231048
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
248 AM PST SAT DEC 23 2006

...HIGH SURF ADVISORY IS CANCELLED...

CAZ006-505-509-514-515-231200-
/O.CAN.KMTR.SU.Y.0013.000000T0000Z-061223T1200Z/
SAN FRANCISCO-
COASTAL NORTH BAY...INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-
MONTEREY BAY...NORTHERN SALINAS VALLEY...HOLLISTER VALLEY...AND
CARMEL VALLEY-BIG SUR COAST-
248 AM PST SAT DEC 23 2006

...HIGH SURF ADVISORY IS CANCELLED...

AT 2 AM...COASTAL BUOYS SHOW SEA SWELL HAVE SUBSIDED BELOW 15
FEET. SEAS WILL RANGE FROM 10 TO POSSIBLY AS HIGH AS 13 FEET TODAY.
THE HIGH SURF ADVISORY HAS BEEN CANCELLED.

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
850 PM PST FRI DEC 22 2006

.DISCUSSION...HIGH CLOUDS ARE BEGINNING TO SPREAD OVER THE
NORTH BAY EARLY THIS EVENING AND SATELLITE IMAGERY SHOWS A BAND OF
THICKER CLOUDS NEARING THE COAST...LIKELY ASSOCIATED WITH A WEAK WARM
FRONT. RADAR INDICATES SOME VERY WEAK RETURNS WITHIN THE APPROACHING
CLOUD BAND. BOTH THE 00Z WRF AND 00Z GFS FORECAST NO MEASURABLE
RAINFALL ACROSS OUR AREA TONIGHT...BUT WOULDNT BE SURPRISED IF THERE
ARE A FEW SPRINKLES FROM SAN MATEO COUNTY NORTH. RAIN CHANCES ARE NOT
EXPECTED TO INCREASE APPRECIABLY UNTIL ABOUT MIDDAY SATURDAY WHEN
THE MAIN FRONTAL BAND SAGS INTO NORTHERN CA. EVEN THEN...THE WRF
KEEPS NEARLY ALL PRECIP NORTH OF OUR AREA AND THE GFS BRINGS RAINFALL
ONLY AS FAR S AS MARIN COUNTY BY LATE TOMORROW AFTERNOON/EARLY
TOMORROW EVENING. SHORTWAVE RIDGING LATE SATURDAY NIGHT AND SUNDAY
WILL REDUCE THE CHANCE OF RAIN EVEN FURTHER. WILL NEED TO CONSIDER
REDUCING POPS FOR SATURDAY NIGHT AND SUNDAY...ESPECIALLY FOR AREAS
SOUTH OF THE GOLDEN GATE.

PRIMARY FORECAST CONCERN AT THE MOMENT IS THE CHRISTMAS DAY AND
CHRISTMAS NIGHT FORECAST. THE GFS CONTINUES TO FORECAST A WET
24 HOURS BETWEEN CHRISTMAS MORNING AND TUESDAY MORNING AS STRONG
WARM ADVECTION DEVELOPS OVER NORTHERN CA AND LIFTS A MOIST AIRMASS
STREAMING IN OFF THE PACIFIC. HOWEVER...THE 00Z RUN OF THE GFS HANGS
THE MORE SERIOUS RAIN UP OVER THE NORTH BAY A BIT LONGER (COMPARED TO
PREVIOUS GFS RUNS)...AND DOES NOT PUSH THE MODERATE TO LOCALLY HEAVY
RAIN S OF THE GOLDEN GATE UNTIL MONDAY EVENING. PRECIP AMOUNTS WITH
THE GFS ARE STILL QUITE IMPRESSIVE...ESPECIALLY IN THE N BAY WHERE
18-24 HOURS OF SOAKING RAINS COULD EASILY ADD UP TO 2-3 INCHES. BUT
THEN THERE IS THE WRF TO CONSIDER. AND IT IS SIGNIFICANTLY DIFFERENT
THAN THE GFS. IN FACT...THE 00Z WRF DOES NOT DEVELOP ANY PRECIP SOUTH
OF SANTA ROSA THROUGH EARLY TUESDAY MORNING. THE WRF OFTEN PERFORMS
POORLY IN WARM ADVECTION PRECIP EVENTS SUCH AS THIS...SO FEEL IT CAN
MOSTLY BE IGNORED. HOWEVER...THE BIG DIFFERENCES IN PRECIP
FORECASTS BETWEEN THE TWO NCEP MODELS RESULTS IN A LOWER LEVEL OF
CONFIDENCE IN OUR FORECAST...PARTICULARLY FOR THE SOUTHERN HALF OF
OUR CWA. FOR NOW WILL CONTINUE TO HEAVILY FAVOR THE GFS SOLUTION...
BUT WILL HAVE TO WATCH TO SEE IF THE GFS CONTINUES ITS CURRENT TREND
OF SLOWING THE SOUTHWARD ADVANCEMENT OF PRECIP.

THE GFS HAS BEEN CONSISTENT ON MOVING RAIN FROM N TO S THROUGH THE
REGION ONCE THE INITIAL PUSH TO THE SOUTH BEGINS LATE MONDAY AND
MONDAY NIGHT. THUS...ALTHOUGH MOST AREAS WILL PROBABLY SEE A PERIOD
OF MODERATE TO LOCALLY HEAVY RAIN OUT OF THIS SYSTEM...LESS
PROLONGED RAINS SOUTH OF THE GOLDEN GATE WILL MEAN SIGNIFICANTLY LESS
OVERALL ACCUMULATION FOR THE SOUTHERN TWO-THIRDS OF OUR REGION
COMPARED TO THE NORTHERN THIRD. WILL ATTEMPT TO FINE-TUNE THE
RAINFALL FORECAST AS WE GET CLOSER TO THE EVENT AND AS MODELS...
HOPEFULLY...COME INTO BETTER AGREEMENT.

DRIER WEATHER IS FORECAST DURING THE MIDDLE PART OF NEXT WEEK AS
RIDGING REDEVELOPS ALOFT. BUT THE PATTERN WILL REMAIN PROGRESSIVE
AND MORE RAIN IS LIKELY BY THE END OF NEXT WEEK...PARTICULARLY IN
THE NORTH.

&&

.AVIATION...HIGH CLOUDS WILL INCREASE OVER THE AREA TONIGHT BUT
CONDITIONS WILL REMAIN VFR THROUGH SATURDAY EXCEPT FOR LOCAL
FOG AROUND STS UNTIL 18Z. WINDS WILL BE LIGHT OVERNIGHT BECOMING SE
LESS THAN 10 KT SATURDAY.

.MTR...WATCHES/WARNINGS/ADVISORIES...
      .TNGT...SCA...PT ARENA TO PIGEON POINT AND MRY BAY
                    AS WELL AS A ROUGH BAR ADVISORY.
      .TNGT...HIGH SURF ADVY...ENTIRE COAST FROM SONOMA COUNTY
                               THRU MONTEREY COUNTY TIL 4 AM.

PUBLIC FORECAST: DYKEMA
AVIATION/MARINE: W PI

NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
815 PM PST FRI DEC 22 2006

CAZ006-505-509-514-515-231400-
BIG SUR COAST-SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-
MONTEREY BAY/NORTHERN SALINAS VALLEY/HOLLISTER VALLEY AND CARMEL
VALLEY-
815 PM PST FRI DEC 22 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR COASTAL SECTIONS OF THE
SAN FRANCISCO AND MONTEREY BAY AREAS.

.DAY ONE...FRIDAY NIGHT AND SATURDAY

A HIGH SURF ADVISORY CONTINUES ALONG THE COAST UNTIL 4 AM SATURDAY
FOR BREAKING WAVES IN EXCESS OF 15 FEET.

* HIGH SURF ADVISORY.....SEE SFOCFWMTR - WHUS46 KMTR FOR DETAILS *

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

PERIODS OF RAIN WILL BE POSSIBLE SUNDAY NIGHT THROUGH EARLY TUESDAY
WITH THE BULK OF THE RAIN LIKELY FALLING ON CHRISTMAS DAY AND
NIGHT. HOLIDAY TRAVEL MAY BE IMPACTED. TRAVELERS SHOULD CHECK THE
LATEST FORECASTS FROM THE NATIONAL WEATHER SERVICE.

CAZ506>508-510>513-516>518-231400-
SOUTHERN SALINAS VALLEY/ARROYO SECO AND LAKE SAN ANTONIO-
SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST-
MOUNTAINS OF SAN BENITO COUNTY AND INTERIOR MONTEREY COUNTY
INCLUDING PINNACLES NATIONAL MONUMENT-NORTH BAY INTERIOR VALLEYS-
NORTH BAY MOUNTAINS-SAN FRANCISCO BAY SHORELINE-
EAST BAY INTERIOR VALLEYS-EAST BAY HILLS AND THE DIABLO RANGE-
SANTA CRUZ MOUNTAINS-SANTA CLARA VALLEY INCLUDING SAN JOSE-
815 PM PST FRI DEC 22 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR INLAND SECTIONS OF THE
SAN FRANCISCO AND MONTEREY BAY AREAS.

.DAY ONE...FRIDAY NIGHT AND SATURDAY

PATCHY DENSE FOG MAY FORM IN THE INLAND VALLEYS LATE FRIDAY
NIGHT AND EARLY SATURDAY...PARTICULARLY IN THE VALLEYS OF THE NORTH
BAY.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

PERIODS OF RAIN ARE POSSIBLE SUNDAY NIGHT THROUGH EARLY TUESDAY
WITH THE BULK OF THE RAIN LIKELY FALLING LATE CHRISTMAS DAY AND
NIGHT. HOLIDAY TRAVEL MAY BE IMPACTED. TRAVELERS SHOULD CHECK THE
LATEST FORECASTS FROM THE NATIONAL WEATHER SERVICE.

DYKEMA