FNUS76 KSTO 090232
FWSSTO

SPOT FORECAST FOR SAN DIMAS ENGINE BURN OVER STUDY...CAL FIRE
NATIONAL WEATHER SERVICE SACRAMENTO CA
732 PM PDT THU SEP 8 2011

FORECAST IS BASED ON IGNITION TIME OF 1400 PDT ON SEPTEMBER
13TH...AND 1200 ON SEPTEMBER 15TH. IF CONDITIONS BECOME
UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE.

.DISCUSSION...
UPPER LEVEL LOW PRESSURE OVER NEVADA WILL CAUSE MODERATE INSTABILITY
OVER THE BURN SITE ON TUESDAY. THUNDERSTORM ACTIVITY IS EXPECTED TO
DEVELOP DURING THE AFTERNOON OVER THE HIGHER TERRAIN TO THE EAST OF
THE BURN SITE. WINDS WILL BE MODERATE AT BEST ON TUESDAY...WITH
LIGHTER WINDS EXPECTED ON THURSDAY.

THE UPPER LEVEL LOW PRESSURE WILL MOVE LITTLE WEDNESDAY AND
THURSDAY...BUT IT IS FORECAST TO WEAKEN. THE AIR MASS WILL NOT BE
AS UNSTABLE AND WINDS ALOFT WILL BE WEAKER. ANY THUNDERSTORM
ACTIVITY IS EXPECTED TO BE CLOSER TO THE SIERRA NEVADA CREST THAN
ON TUESDAY.


.TUESDAY THE 13TH...

SKY/WEATHER.........MOSTLY SUNNY IN THE MORNING...PARTLY CLOUDY WITH
                    A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IN
                    THE AFTERNOON EAST OF THE BURN SITE.
MAX TEMPERATURE.....90-95.
MIN HUMIDITY........20-25 PERCENT.
WIND (20 FT)........
   SLOPE/VALLEY.....SOUTHWEST 2 TO 6 MPH BECOMING WEST 5 TO 10 MPH
                    IN THE AFTERNOON.
   RIDGETOP.........NORTHWEST 6 TO 12 MPH.
MIXING HEIGHT.......RISING TO 5000 FT AGL.
MIXING WINDS........SOUTHWEST TO WEST 5 MPH.

.THURSDAY THE 15TH...

SKY/WEATHER.........SUNNY.
MAX TEMPERATURE.....92-97.
MIN HUMIDITY........17-22 PERCENT.
WIND (20 FT)........
   SLOPE/VALLEY.....SOUTHWEST TO WEST 4 TO 8 MPH.
   RIDGETOP.........SOUTH TO SOUTHWEST 5 TO 10 MPH.
MIXING HEIGHT.......RISING TO 4500 TO 5000 FT AGL.
MIXING WINDS........SOUTHWEST AT 5 MPH.


FORECASTER...JHM
REQUESTED BY...BILL BAXTER
REASON FOR REQUEST...PRESCRIBED
.TAG 20110913.SANDI.01/STO

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