FNUS76 KSEW 020017
FWSSEW

SPOT FORECAST FOR RAINBOW BRIDGE...NPS NORTH CASCADES
NATIONAL WEATHER SERVICE SEATTLE WA
517 PM PDT SUN AUG 1 2010

FORECAST IS BASED ON REQUEST TIME OF 1743 MDT ON AUGUST 01.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE IN SEATTLE.

.DISCUSSION...CUMULUS BUILDUPS WILL LIKELY TAKE PLACE ON RIDGES
EAST OF THE FIRE ON MONDAY...BUT PREVAILING WESTERLY FLOW WILL
LIKELY STEER ANY THUNDERSTORMS AWAY FROM THE FIRE. A TURN TO MORE
SOUTHELRY FLOW ALOFT ON TUESDAY WOULD BE MORE LIKELY TO STEER
THUNDERSTORM DEVELOPMENT CLOSER TO THE FIRE AND INCREASE THE RISK
OF LIGHTNING. OTHERWISE...A GRADUAL WARMING TREND IS EXPECTED
THROUGH THURSDAY. WEAKENING PRESSURE GRADIENTS ACROSS THE CASCADES
WILL ALLOW SOUTHEASTERLY WINDS BLOWING UP THE STEHEKIN VALLEY EACH
AFTERNOON TO BECOME INCREASINGLY DOMINANT THROUGH WEDNESDAY.

 FORECAST FOR 20 FOOT WIND SPEED (VALLEYS AND RIDGE TOPS) ARE 10
 MINUTE AVERAGES REFLECTING RAWS WINDS.

.TODAY...

SKY/WEATHER.........MOSTLY SUNNY IN THE MORNING. A FEW CUMULUS
                    BUILDUPS IN THE AFTERNOON. A THUNDERSTORM
                    CANNOT BE RULED OUT BUT IS UNLIKELY.
CWR (>0.20")........5%.
MAX TEMPERATURE.....88 AT 1200 FEET...71 AT 4500 FEET.
MIN HUMIDITY........26 PERCENT AT 1200 FEET...44 PERCENT AT
                    4500 FEET.
WIND (20 FT)........UPSLOPE THEN UPVALLEY 5 TO 7 MPH...
                    BECOMING NORTHWEST 7 TO 9 MPH AROUND
                    1500 PDT WITH GUSTS TO 20 MPH.
HAINES INDEX........MID-LEVEL....4 OR LOW.
                    HIGH-LEVEL...3 OR VERY LOW.
LAL.................2.

.TONIGHT...

SKY/WEATHER.........PARTLY CLOUDY. A SLIGHT CHANCE OF AN EARLY
                    EVENING SHOWER OR THUNDERSTORM.
CWR (>0.20")........5%.
MIN TEMPERATURE.....56 AT 1200 FEET...50 AT 4500 FEET.
MAX HUMIDITY........75-80 PERCENT AT 1200 FEET...90 PERCENT AT
                    4500 FEET.
WIND (20 FT)........NORTHWEST WINDS 3 TO 6 MPH EARLY IN THE
                    EVENING...BECOMING DOWNSLOPE/DOWNVALLEY
                    1 TO 3 MPH BY LATE EVENING.
HAINES INDEX........MID-LEVEL....4 OR LOW.
                    HIGH-LEVEL...2 OR VERY LOW.
LAL.................2.

.TUESDAY...

SKY/WEATHER.........MOSTLY SUNNY IN THE MORNING. CUMULUS
                    BUILDUPS IN THE AFTERNOON WITH A CHANCE
                    OF A SHOWER OR THUNDERSTORM.
CWR (>0.20")........10%.
MAX TEMPERATURE.....91 AT 1200 FEET...74 AT 4500 FEET.
MIN HUMIDITY........23 PERCENT AT 1200 FEET....40 PERCENT AT
                    4500 FEET.
WIND (20 FT)........UPSLOPE THEN UPVALLEY 5 TO 7 MPH...
                    BECOMING NORTHWEST 7 TO 9 MPH AROUND
                    1800 PDT.
HAINES INDEX........MID-LEVEL....5 OR MODERATE.
                    HIGH-LEVEL...2 OR VERY LOW.
LAL.................2.

.FORECAST DAYS 3 THROUGH 5...
.WEDNESDAY...
MOSTLY CLOUDY. CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS AROUND 57.
HIGHS AROUND 94. UPSLOPE/UPVALLEY WINDS 5 TO 8 MPH.
.THURSDAY...
PARTLY CLOUDY. CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS AROUND
59. HIGHS AROUND 96. UPSLOPE/UPVALLEY WINDS 5 TO 8 MPH...THEN
NORTHWEST WINDS 4 TO 7 MPH.
.FRIDAY...
PARTLY CLOUDY. CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS AROUND 60.
HIGHS AROUND 92. NORTHWEST WINDS 8 TO 11 MPH WITH GUSTS NEAR 25 MPH.

$$
FORECASTER...HANER
REQUESTED BY...FBAN
TYPE OF REQUEST...WILDFIRE
.TAG 20100801.RAINB.02/SEW