FNUS76 KSEW 070239
FWSSEW

SPOT FORECAST FOR BIG HUMP...USFS
NATIONAL WEATHER SERVICE SEATTLE WA
739 PM PDT TUE SEP 6 2011

FORECAST IS BASED ON REQUEST TIME OF 1921 PDT ON SEPTEMBER 06.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE IN SEATTLE.

...RED FLAG WARNING IN EFFECT ON WEDNESDAY FROM 11 AM TO MIDNIGHT
FOR A DRY AND UNSTABLE AIR MASS...

.DISCUSSION...A STRONG UPPER LEVEL HIGH PRESSURE RIDGE WILL
PERSIST OVER THE NORTHWEST INTO THIS WEEKEND. AT TIMES...INCLUDING
WEDNESDAY...THIS WILL PUSH A STRONG SUBSIDENCE INVERSION DOWN
INTO THE LOWER ELEVATIONS...LEAVING MID AND HIGH ELEVATIONS...
GENERALLY ABOVE 2000 FEET...EXPOSED TO AN EXTREMELY DRY AND
UNSTABLE AIR MASS. MID-LEVEL HAINES 6 CONDITIONS ARE FORECAST FOR
SEVERAL DAYS BEGINNING ON WEDNESDAY. A THERMAL PRESSURE TROUGH IS
EXPECTED TO DEVELOP ALONG THE COAST THIS WEEKEND...ALLOWING
INCREASING EAST WINDS...NEAR RECORD HIGH TEMPERATURES...AND
INCREASING INSTABILITY IN THE LOWLANDS.

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

.WEDNESDAY...

SKY/WEATHER.........SUNNY.
CWR.................0%.
MAX TEMPERATURE.....VALLEY BOTTOM AROUND 83.
                    UPPER ELEVATIONS AROUND 77.
MIN HUMIDITY........AROUND 25 PERCENT ALL ELEVATIONS.
WIND (20 FT)........
 VALLEY BOTTOM......LIGHT WIND IN THE MORNING BECOMING UPSLOPE/
                    UPVALLEY 4-8 MPH AFTER 1000 AM.
 MID-SLOPES/RIDGES..SOUTH-SOUTHWEST WIND 5-10 MPH.
MIXING HEIGHT.......RISING IN THE AFTERNOON TO 7000 FT MSL.
TRANSPORT WINDS.....DOWNVALLEY 3 MPH UNTIL 1100. AFTER 1100...SOUTH
                    TO SOUTHWEST 5-10 MPH ONCE SMOKE RISES ABOVE THE
                    RIDGETOPS.
HAINES INDEX........MID LEVEL...6 OR HIGH.
                    HIGH LEVEL...5 OR MODERATE.
LAL.................1.
RAINFALL AMOUNT.....0.00 INCHES.

.TONIGHT...

SKY/WEATHER.........CLEAR.
CWR.................0%.
MIN TEMPERATURE.....VALLEY BOTTOM...50-52.
                    MID SLOPES...58-62 ABOVE THE NIGHTTIME INVERSION.
MAX HUMIDITY........VALLEY BOTTOM...70-80 PERCENT.
                    MID SLOPES ABOVE NIGHTTIME INVERSION...40-50 PERCENT.
WIND (20 FT)........
 VALLEY BOTTOM......DOWNSLOPE/DOWNVALLEY 2-4 MPH BECOMING LIGHT.
 MID SLOPES/RIDGES..SOUTH 3-5 MPH.
MIXING HEIGHT.......NEAR 0 FT AGL WITH SMOKE SINKING INTO VALLEY.
TRANSPORT WINDS.....WESTERLY DOWNVALLEY 3-5 MPH.
HAINES INDEX........MID-LEVEL...6 OR HIGH.
                    HIGH-LEVEL...5 OR MODERATE.
LAL.................1.
RAINFALL AMOUNT.....0.00 INCHES.

.THURSDAY...

SKY/WEATHER.........SUNNY.
CWR.................0%.
MAX TEMPERATURE.....VALLEY BOTTOM...AROUND 86.
                    UPPER ELEVATIONS...AROUND 80.
MIN HUMIDITY........28-33 PERCENT ALL ELEVATIONS.
WIND (20 FT)........
 VALLEY BOTTOM......LIGHT WIND BECOMING UPSLOPE/UPVALLEY 4 TO 8 MPH.
 MID SLOPES/RIDGES..LIGHT WIND.
MIXING HEIGHT.......RISING TO 6500 FEET MSL IN THE AFTERNOON.
TRANSPORT WINDS.....DOWNVALLEY 3 MPH UNTIL 1000. AFTER 1000...WEST 5 MPH ONCE
                    SMOKE RISES ABOVE THE RIDGETOPS.
HAINES INDEX........MID LEVEL...6 OR MODERATE.
                    HIGH LEVEL..5 OR MODERATE.
LAL.................1.
RAINFALL AMOUNT.....0.00 INCHES.

$$
FORECASTER...ALBRECHT
REQUESTED BY...RITA CHANDLER
TYPE OF REQUEST...WILDFIRE
.TAG 20110906.BIGHU.01/SEW