Friday, February 28, 2014

Flash flood and surf advisories for Northern California coast

The national Weather service has issued a flash flood warning for Santa Cruz, Monterey and San Benito Countries as of Friday morning.

NWS officials said Big Sur is at the highest risk of mudslides and landslides during this storm because it was hit by a 4.4 magnitude earthquake Thursday and a 900 acre wildfire in December.

Sudden rain could cause mudslides to happen in those areas of Los Padres National Forest.

"Of particular concern it he Pfeiffer burn scar and the Sycamore Canyon within the burn scar perimeter," the NWS said. "Excessive rainfall may have a higher likelihood of producing debris flows and slides."

"A magnitude 4.4 earthquake occurred south of the Pfeiffer Area on the San Simeon Fault offshore...immediately west of the burn scar," the NWS said.

end partial quote from www.ksbw.com
begin second part of quote from same online article


-- National Weather Service High Surf and Flash Flood Advisory --
COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
516 AM PST FRI FEB 28 2014
WESTERLY SWELL REMAINS ON TRACK TO IMPACT LOCAL BEACHES SOUTH OF
SAN FRANCISCO FRIDAY EVENING TO SATURDAY AFTERNOON. SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-SOUTHERN MONTEREY BAY AND BIG SUR COAST
...HIGH SURF ADVISORY REMAINS IN EFFECT FROM 8 PM THIS EVENING TO
3 PM PST SATURDAY...
WAVES AND SURF...WESTERLY SWELLS BETWEEN 14 AND 16 FEET WITH A PERIOD OF AROUND 14 SECONDS. LOCAL BREAKERS UP TO 20 FEET POSSIBLE. HIGHEST SWELLS WILL BE SOUTH OF POINT PINOS.
TIMING...FRIDAY EVENING INTO SATURDAY AFTERNOON.
IMPACTS...HIGHER THAN NORMAL SURF ESPECIALLY ALONG WEST AND SOUTHWESTERLY FACING BEACHES. IN ADDITION...THERE WILL BE A HEIGHTENED RISK OF RIP CURRENTS AND SNEAKER WAVES.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A HIGH SURF ADVISORY MEANS THAT HIGH SURF WILL AFFECT BEACHES IN THE ADVISORY AREA...PRODUCING RIP CURRENTS AND LOCALIZED BEACH EROSION.
FLOOD WATCH
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA 826 PM PST THU FEB 27 2014 SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
826 PM PST THU FEB 27 2014
...FLASH FLOOD WATCH REMAINS IN EFFECT FROM MIDNIGHT PST TONIGHT THROUGH LATE FRIDAY NIGHT...
THE FLASH FLOOD WATCH CONTINUES FOR A PORTION OF CALIFORNIA...INCLUDING THE FOLLOWING AREAS...SANTA LUCIA MOUNTAINS AND LOS PADRES NATIONAL FOREST AND SOUTHERN MONTEREY BAY AND BIG SUR COAST.
FROM MIDNIGHT PST TONIGHT THROUGH LATE FRIDAY NIGHT
A SECOND SURGE OF MOISTURE IS SET TO REACH THE GREATER MONTEREY BAY AREA LATE THURSDAY EVENING... BRINGING UPWARDS OF 8 INCHES TO HIGHER ELEVATION AREAS IN THE SANTA LUCIA MOUNTAINS OVER A 24 TO 36 HOUR PERIOD. TOTAL RAINFALL AND RAINFALL RATES MAY BE HIGH ENOUGH TO ENGENDER FLASH FLOODING IN SMALL CREEKS AND DEBRIS FLOWS IN SATURATED... STEEPER TERRAIN.
OF PARTICULAR CONCERN IS THE PFEIFFER FIRE BURN SCAR AND SYCAMORE CANYON AND OTHER LOCAL DRAINAGES WITHIN THE BURN SCAR PERIMETER. EXCESSIVE RAINFALL MAY HAVE A HIGHER LIKELIHOOD OF PRODUCING DEBRIS FLOWS AND SLIDES IN THIS AREA. MID-MORNING THURSDAY A MAGNITUDE 4.4 EARTHQUAKE OCCURRED SOUTH OF THE PFEIFFER AREA ON THE SAN SIMEON FAULT OFFSHORE. THE SAN SIMEON SYSTEM SHARES LINEAMENTS WITH THE SAN GREGORIO SYSTEM JUST OFFSHORE AND IMMEDIATELY WEST OF THE BURN SCAR. ANY FURTHER SEISMIC ADJUSTMENT OF SIGNIFICANT MAGNITUDE THAT OCCURS LOCAL TO THE PFEIFFER BURN SCAR DURING THE COURSE OF FORECAST PRECIPITATION MAY BE SUFFICIENT TO ACCENTUATE DEBRIS FLOW POTENTIAL. EXTRA CAUTION AND PREPAREDNESS IS URGED IN LIGHT OF THIS... AS WELL AS THE ANTECEDENT CONDITIONS FROM THE RAINFALL THAT HAS ALREADY FALLEN.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING AND OR LOCALIZED DEBRIS FLOWS AND SLOPE
INSTABILITY. FLASH FLOODING IS A VERY DANGEROUS SITUATION. YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.

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