Flash Flood Warning 3, NWS San Francisco Bay Area, CA

000 
WGUS76 KMTR 021445
FFSMTR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
645 AM PST MON MAR 2 2009

CAC053-021615-
/O.CON.KMTR.FF.W.0003.000000T0000Z-090302T1615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONTEREY CA-
645 AM PST MON MAR 2 2009

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 AM PST FOR THE 
BURN AREAS OF MONTEREY COUNTY...

AT 630 AM PST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE RAINFALL OCCURRING OVER A LARGE PORTION OF THE BURN AREAS.

ADDITIONALLY...THE BIG SUR RAWS REPORTED MORE THAN TWO TENTHS OF AN 
INCH IN 15 MINUTES A COUPLE OF TIMES OVER THE PAST 90 MINUTES WHILE 
THREE SEPARATE GAGES HAVE RECORDED MORE THAN 2 INCHES OF RAIN IN THE 
SAME AMOUNT OF TIME. BOTH OF THESE VALUES EXCEED THRESHOLDS FOR 
DEBRIS FLOWS TO BE TRIGGERED.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO SYCAMORE
FLAT...PICO BLANCO CAMPGROUND...JAMESBURG...BIG SUR VILLAGE...ARROYO
SECO AND ANDREW MOLERA STATE PARK

MUD SLIDES AND ROCK SLIDES CAN POTENTIALLY TRAP AND KILL PEOPLE 
CAUGHT IN THEIR PATH.

IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE UP TO HIGHER GROUND 
TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING 
WHEN WATER BEGINS RISING.

LAT...LON 3608 12163 3613 12165 3619 12171 3625 12184
      3636 12188 3639 12171 3639 12168 3636 12162
      3636 12158 3630 12142 3622 12133 3612 12123
      3593 12143

$$

BELL

000 
WGUS76 KMTR 021610
FFSMTR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SAN FRANCISCO CA
810 AM PST MON MAR 2 2009

CAC053-021616-
/O.EXP.KMTR.FF.W.0003.000000T0000Z-090302T1615Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MONTEREY CA-
810 AM PST MON MAR 2 2009

...THE FLASH FLOOD WARNING WILL EXPIRE AT 815 AM PST FOR THE BURN
AREAS OF MONTEREY COUNTY...

AS OF 8:05 AM...NATIONAL WEATHER SERVICE RADAR AND AREA RAIN GAUGES 
INDICATE THAT HEAVY RAINS OVER THE BURN AREA HAVE DIMINISHED. 
THEREFORE...THE FLASH FLOOD WARNING WILL BE ALLOWED TO EXPIRE. 
HOWEVER...SHOWERS ARE EXPECTED TO CONTINUE THE REST OF THE DAY AS 
THE MAIN STORM SYSTEM REMAINS OFF THE COAST. PERSONS IN AND AROUND 
THE BURN AREA NEED TO REMAIN ALERT IN THE EVENT FLASH FLOODING OR 
DEBRIS FLOWS OCCUR OR IF A NEW FLASH FLOOD WARNING IS ISSUED.

LAT...LON 3608 12163 3613 12165 3619 12171 3625 12184
      3636 12188 3639 12171 3639 12168 3636 12162
      3636 12158 3630 12142 3622 12133 3612 12123
      3593 12143
TIME...MOT...LOC 1606Z 180DEG 0KT 3624 12159

$$

MEHLE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
415 AM PST MON MAR 2 2009

.DISCUSSION...AS OF 3:25 AM PST MONDAY...CONTINUED UNSETTLED
WEATHER ON TAP FOR THE NEXT SEVERAL DAYS.

PLENTY TO TALK ABOUT THIS MORNING. RIGHT OFF THE BAT...THE FIRST ITEM
TO DEAL WITH WERE THE WINDS ROARING IN PORTIONS OF THE CWA. LOS GATOS
WAS GUSTING TO AROUND 60 MPH WHILE POINT REYES AND INVERNESS WERE
BOTH OVER 40 MPH. ON TOP OF THAT SEVERAL OTHER SENSORS SCATTERED
AROUND ALL HAD IMPRESSIVE NUMBERS. EVEN SFO GOT IN ON THE ACTION AS
IT WENT FROM VARIABLE 3 KTS ON ONE OBSERVATION TO A GUST CLOSE TO 40
KT. WHAT IS CAUSING THE WIND IS A COMBINATION OF AN APPROACHING COLD
FRONT AT THE SURFACE ALONG WITH WINDS JUST ABOVE THE SURFACE THAT ARE
RACING AT 40 TO 55 KT. THE BIG QUESTION YESTERDAY WAS WHETHER OR NOT
THE WINDS WOULD COME DOWN TO THE SURFACE. WE OBVIOUSLY GOT THE ANSWER
LOUD AND CLEAR. ALONG WITH THE WINDS...RAIN HAS CONTINUED THROUGH THE
OVERNIGHT HOURS. RAINFALL RATES HAVE NOT BEEN IMPRESSIVE ALTHOUGH A
FEW SPOTS IN THE BURN AREAS WERE STARTING TO APPROACH VALUES THAT
CAUSE SOME CONCERN FOR DEBRIS FLOWS. THANKFULLY...BEFORE THEY WENT
OVER THE VALUES WE LOOK FOR...THE RAINS BRIEFLY ENDED.

SYNOPTICALLY THE SETUP PLACES A LOW WELL OFF THE WASHINGTON/BC COAST
THAT CAN CLEARLY BE SEEN BY IR SATELLITE. THIS LOW IS LOCATED
MIDWAY IN A LONGWAVE TROUGH THAT STRETCHES FROM THE ARCTIC OCEAN
ALL OF THE WAY TO 28N -- OR A DISTANCE OF OVER 6000 KM! AS LONG AS
THE TROUGH REMAINS OFF THE COAST AND SYSTEMS CAN KEEP DROPPING DOWN
FROM THE NORTH SHOWERS WILL REMAIN IN THE FORECAST.

THEREFORE...TWO MAIN HIGHLIGHTS WITH THE CURRENT FORECAST PACKAGE.
THE FIRST ONE IS WITH THE WINDS. THERE IS FAIRLY GOOD MODEL
AGREEMENT THAT WINDS WILL START TO BACK OFF THROUGH THE MORNING
HOURS AS THE FRONT GOES ACROSS BEFORE PICKING UP AGAIN LATE THIS
AFTERNOON AS THE PRESSURE GRADIENTS START TO RAMP BACK UP. IN
ORDER TO MINIMIZE CONFUSION...DECISION WAS MADE TO SIMPLY EXTEND THE
WIND ADVISORY FOR OUR USUAL SPOTS PLUS THE COASTAL NORTH BAY THROUGH
TUESDAY MORNING INSTEAD OF HAVING IT END THIS MORNING AND BRINGING IT
BACK UP THIS AFTERNOON. FOR AREAS IN THE ADVISORY LOOK FOR A SLOW
DECREASE IN SPEEDS THROUGH EARLY AFTERNOON AND THEN ANOTHER ROUND
OF HIGHER VALUES BY LATE IN THE AFTERNOON. URBAN LOCATIONS WILL
LIKELY SEE GUSTY WINDS THROUGH THE DAY TODAY ESPECIALLY BY THE
LATE AFTERNOON RUSH. WITH ALL OF THE RECENT RAIN THE WIND WILL ALSO
CAUSE SOME TREES TO TOPPLE IN LOCATIONS WHERE THE SOIL IS VERY WET.
THE CHP PAGE TONIGHT ALREADY HAD SEVERAL REPORTS OF TREES DOWN IN
OUR AREA.

THE SECOND CONCERN IS STILL RAINFALL. RADAR RETURNS TO THIS POINT
HAVE NOT BEEN IMPRESSIVE AND A QUICK SCAN OF CURRENT READINGS DOES
NOT SHOW ANY PROBLEM AREAS. SOME OF THE UNOFFICIAL TOTALS FOR THE
LAST SIX HOURS INCLUDE UMUNHUM WITH 1.19" ...MOUNT ST HELENA
WITH .98" ...ANDERSON PEAK IN MONTEREY COUNTY WITH .87" AND BEN
LOMOND WITH .66". OVER THE NEXT THREE DAYS MULTIPLE IMPULSES WILL
ROTATE AROUND THE LOW OFF THE COAST AND MOVE INTO OUR AREA.
ALTHOUGH PW VALUES WILL BE QUITE A BIT LESS THAN WHAT THEY WERE
YESTERDAY...INSTABILITY IS MUCH HIGHER (LIFTED VALUES DOWN TO
MINUS 1 WITH CAPES CLOSE TO 500 J/KG) OVER THE NEXT 36 HOURS WHICH
WILL HELP TO INCREASE THE CHANCE OF CONVECTIVE ACTIVITY ALONG WITH A
SHOT AT SMALL HAIL. AS IS ALWAYS THE CASE WITH THUNDERSTORM
POTENTIAL...THE BIGGEST CONCERN WILL BE THE POSSIBILITY OF HEAVY RAIN
WHICH COULD LEAD TO LOCALIZED FLOODING. THE NORTH BAY IS STILL
EXPECTED TO HAVE THE GREATEST RAINFALL TOTALS THROUGH TUESDAY WITH
.75 TO 2 INCHES EXPECTED. AROUND SF BAY LOOK FOR .5 TO 1.5". FURTHER
TO THE SOUTH .25 TO .75" IS IN THE CARDS WITH UP TO AN INCH POSSIBLE
OVER HIGHER COASTAL RANGES.

DUE TO THE FAR NORTHERN ORIGIN OF THE IMPULSES SNOW LEVELS WILL DROP
ACROSS THE BOARD. STILL LOOKS LIKE TUESDAY NIGHT THROUGH THURSDAY
NIGHT SNOW WILL BE POSSIBLE DOWN TO 3000 FEET WITH A MIX DOWN TO
2500 FEET. THERE IS AN OUTSIDE SHOT THAT THE RAIN/SNOW MIX COULD
DROP DOWN TO 2000 FEET OVER THE NORTH BAY MOUNTAINS WHERE 700 MB
TEMPERATURES ARE EXPECTED TO DROP AS LOW AS -13C. SNOWFALL TOTALS
ARE NOT EXPECTED TO BE IMPRESSIVE AS THE SYSTEM WILL START TO BECOME
MORE AND MORE MOISTURE STARVED BEYOND TUESDAY.

FURTHER OUT...FORECAST CONFIDENCE IS LOW AS THE MODELS ARE SHOWING A
WIDE RANGE OF SOLUTIONS FROM CONTINUED UNSETTLED...WARMER AND DRY...
AND CONTINUED COOL AND DRY. AT THIS TIME THE GRIDS FOR FRIDAY
ONWARD ARE CLIMATOLOGY NUDGED TOWARD THE DRY SIDE WITH TEMPERATURES
A FEW DEGREES WITHIN NORMAL VALUES.
&&

.AVIATION...AS OF 4:15 AM PST MONDAY...A COLD FRONTAL SYSTEM WILL
SLIDE ACROSS THE AREA THIS MORNING GENERATING ADDITIONAL SHOWERS.
LOCALLY GUSTY WINDS FROM LAST EVENING HAVE GENERALLY SETTLED DOWN
AT THIS HOUR. SURFACE WINDS REMAIN LINKED TO LOW LEVEL WINDS THROUGH
THE DAY. STEEPENED PRESSURE GRADIENTS WILL HELP LIFT WINDS AGAIN BY
THIS AFTERNOON AND THROUGH THE EVENING. GUIDANCE SHOWS AN UPTREND IN
WINDS BY THE EVENING. MVFR CONDITIONS ARE FORECAST TODAY WITH
SHOWERS MOVING THROUGH THE AREA.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
    .TDAY...WIND ADVISORY FOR COASTAL NORTH BAY...NORTH AND
            EAST BAY HILLS...AND SANTA CRUZ MOUNTAINS.
         ...SCA...ALL COASTAL WATERS AND SF BAY.

&&

PUBLIC FORECAST: BELL
AVIATION/MARINE: CANEPA

NWS ON THE WEB AT WEATHER.GOV/SANFRANCISCO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
406 AM PST MON MAR 2 2009

CAZ006-505>513-516>518-528>530-031215-
SAN FRANCISCO-
COASTAL NORTH BAY...INCLUDING POINT REYES NATIONAL SEASHORE-
NORTH BAY INTERIOR VALLEYS-NORTH BAY MOUNTAINS-
SAN FRANCISCO BAY SHORELINE-SAN FRANCISCO PENINSULA COAST-
EAST BAY INTERIOR VALLEYS-EAST BAY HILLS AND DIABLO RANGE-
SANTA CRUZ MOUNTAINS-SANTA CLARA VALLEY...INCLUDING SAN JOSE-
SOUTHERN SALINAS VALLEY...ARROYO SECO...AND LAKE SAN ANTONIO-
SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST-
MOUNTAINS OF SAN BENITO AND INTERIOR MONTEREY COUNTY INCLUDING
PINNACLES NATIONAL MONUMENT-
NORTHERN SALINAS VALLEY...HOLLISTER VALLEY...AND CARMEL VALLEY-
NORTHERN MONTEREY BAY-SOUTHERN MONTEREY BAY AND BIG SUR COAST-
406 AM PST MON MAR 2 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SAN FRANCISCO BAY AREA AND
MONTEREY BAY AREA.

.DAY ONE...MONDAY AND MONDAY NIGHT

A PACIFIC STORM SYSTEM WILL SPREAD SHOWERS THROUGH OUR AREA
TODAY. ALTHOUGH THE HEAVIEST RAINFALL ALONG WITH A SLIGHT CHANCE
OF THUNDERSTORMS WITH SMALL HAIL IS EXPECTED NORTH OF SAN
FRANCISCO ALL LOCATIONS IN THE DISTRICT WILL HAVE A SHOT AT BRIEF
HEAVY RAIN. PERSONS IN THE BURN AREAS SHOULD CLOSELY MONITOR THE
LATEST FORECASTS.THIS STORM SYSTEM WILL ALSO CONTINUE GUSTY WINDS
PARTICULARLY OVER THE COAST NORTH BAY AND HIGHER ELEVATIONS AROUND
OUR AREA.

* WIND ADVISORY.....SEE SFONPWMTR WGUS76 KMTR FOR DETAILS *

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

EXPECT CONTINUED UNSETTLED WEATHER THROUGH THE MIDDLE HALF OF THE
WEEK. THERE ARE SIGNS THAT DRIER WEATHER IS ON TAP TOWARD THE END
OF THE WEEK.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS PER STANDARD OPERATING PROCEDURES.

BELL