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2 products issued by NWS for:

Red Flag Warning

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
453 AM PDT THU SEP 26 2013

CAZ507-511-270000-
/O.CON.KMTR.FW.W.0004.000000T0000Z-130927T2200Z/
NORTH BAY MOUNTAINS-EAST BAY HILLS AND DIABLO RANGE-
453 AM PDT THU SEP 26 2013

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 3 PM PDT FRIDAY FOR
GUSTY NORTH WINDS AND LOWERING HUMIDITY VALUES...

* AFFECTED AREA: FIRE ZONE 507 NORTH BAY MOUNTAINS...FIRE ZONE
  511 EAST BAY HILLS AND DIABLO RANGE. THIS INCLUDES ALL HILLS
  IN THE NORTH AND EAST BAY ABOVE 1000 FEET INCLUDING MOUNT
  TAMALPAIS...MOUNT DIABLO AND MOUNT SAINT HELENA.

* TIMING: STRONG WINDS DEVELOPING LAST NIGHT WILL PERSIST THROUGH
  THIS MORNING. WINDS WILL INCREASE AGAIN TONIGHT AND CONTINUE
  INTO EARLY FRIDAY.

* WIND: NORTHERLY WINDS 15 TO 25 MPH WITH FREQUENT GUSTS 35 TO 45
  MPH OVER THE HIGHEST PEAKS OF NAPA COUNTY AS WELL AS MOUNT SAINT
  HELENA AND MOUNT DIABLO. STRONGEST WINDS ARE EXPECTED THROUGH
  THIS MORNING AND THEN AGAIN LATE THIS EVENING THROUGH FRIDAY
  MORNING.

* HUMIDITY: HUMIDITY VALUES WILL LOWER TO 30-40% BY THIS MORNING
  ...THEN CONTINUE TO DRY OUT TO LESS THAN 30% FROM THIS AFTERNOON
  THROUGH FRIDAY WITH NO OVERNIGHT HUMIDITY RECOVERY EXPECTED
  THURSDAY NIGHT.

* IMPACTS: ANY NEW IGNITIONS WILL HAVE THE POTENTIAL TO PRODUCE
  WIND DRIVEN FIRE BEHAVIOR THIS MORNING. WARMING AND DRYING
  ALONG WITH PERSISTENT OFFSHORE FLOW WILL MAKE SUPPRESSION
  DIFFICULT. SIMILAR WEATHER EVENTS IN THE PAST HAVE BROUGHT DOWN
  POWER LINES AND OTHER IGNITION SOURCES THAT HAVE STARTED NEW
  FIRES. EXTRA CARE WITH IGNITION SOURCES IS URGED.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES CAN
CONTRIBUTE TO EXTREME FIRE BEHAVIOR.

&&

$$



Hazardous Weather Outlook

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
458 AM PDT THU SEP 26 2013

CAZ507-511-271300-
NORTH BAY MOUNTAINS-EAST BAY HILLS AND DIABLO RANGE-
458 AM PDT THU SEP 26 2013

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

.DAY ONE...THURSDAY AND THURSDAY NIGHT

GUSTY NORTHERLY WINDS WILL CONTINUE THIS MORNING WITH GUSTS 35 TO
45 MPH POSSIBLE ACROSS RIDGES. A RED FLAG WARNING IS IN EFFECT.

*  RED FLAG WARNING...SEE SFORFWMTR WWUS86 KMTR FOR DETAILS *

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

GUSTY NORTHERLY WINDS WILL CONTINUE IN THE HILLS THROUGH FRIDAY
MORNING. IN ADDITION...LOWERING HUMIDITY VALUES ARE FORECAST TO
OCCUR THROUGH FRIDAY. A RED FLAG WARNING REMAINS IN EFFECT
THROUGH FRIDAY AFTERNOON.

*  RED FLAG WARNING...SEE SFORFWMTR WWUS86 KMTR FOR DETAILS *

AFTER THE OFFSHORE WIND EVENT...SEASONABLY WEATHER IS FORECAST
OVER THE WEEKEND AND INTO EARLY NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

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

$$



U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
E-mail: w-nws.webmaster@noaa.gov
Page last modified: May 16, 2007
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