FNUS75 KSLC 172202
FWSSLC

SPOT FORECAST FOR TWITCHELL CANYON
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
402 PM MDT TUE AUG 17 2010

.DISCUSSION...HIGH PRESSURE IN PLACE ACROSS THE AREA TODAY WILL
MOVE EAST TONIGHT ALLOWING A SOUTHWESTERLY FLOW ALOFT TO
OVERSPREAD THE AREA. THIS WILL QUICKLY BRING MOISTURE NORTHWARD
OUT OF ARIZONA...AND COMBINED WITH A WEAK WEATHER DISTURBANCE
WILL RESULT IN A CONSIDERABLE THREAT FOR SHOWERS AND THUNDERSTORMS
DURING THE AFTERNOON AND EVENING HOURS WEDNESDAY. WETTING RAINS
CAN BE EXPECTED WITH MOST STORMS WHICH DEVELOP.

A STRONGER WEATHER SYSTEM IS EXPECTED TO PASS THROUGH THE AREA
THURSDAY BRINGING A CONTINUED THREAT FOR SHOWERS AND THUNDERSTORMS.
IN THE WAKE OF THIS SYSTEM WESTERLY FLOW WILL ALLOW FOR A WARMING
AND DRYING TREND FRIDAY AND SATURDAY...WITH A SMALL CHANCE FOR
SHOWERS AND THUNDERSTORMS EACH DAY. BY SUNDAY IT APPEARS MOISTURE
WILL BEGIN TO INCREASE ONCE AGAIN AS SOUTHWESTERLY FLOW
REDEVELOPS. THIS MOISTURE IS EXPECTED TO REMAIN IN PLACE THROUGH
THE FIRST HALF OF NEXT WEEK.

.REST OF TODAY...
LAL...................1.
HAINES INDEX..........5 ..MODERATE.
CLEARING INDEX........1000.
SKY/WEATHER...........MOSTLY SUNNY (20-30 PERCENT CLOUD COVER).
MAX TEMPERATURE.......82-85 NEAR 8000 FEET...67-70 NEAR 10000 FEET.
MIN HUMIDITY..........15-18 PERCENT NEAR 8000 FEET...SIMILAR ALONG
                      RIDGELINES.
WIND (20 FT)..........SOUTHWEST/UPSLOPE 6-12 MPH. RIDGELINE WINDS
                      WEST 7-14 MPH GUSTING NEAR 20 MPH.

.TONIGHT...
LAL...................1.
HAINES INDEX..........3 ..VERY LOW.
SKY/WEATHER...........PARTLY CLOUDY (35-45 PERCENT CLOUD COVER). A
                      SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS.
MIN TEMPERATURE.......57-59.
MAX HUMIDITY..........72-74 PERCENT.
WIND (20 FT)..........DOWNSLOPE 4-9 MPH. RIDGELINE WINDS SOUTHWEST
                      6-12 MPH.

.OUTLOOK FOR WEDNESDAY...
LAL...................2 UNTIL NOON...THEN 5.
HAINES INDEX..........3 ..VERY LOW.
CLEARING INDEX........1000+.
SKY/WEATHER...........PARTLY CLOUDY (55-65 PERCENT CLOUD COVER). A
                      SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IN
                      THE MORNING...THEN SHOWERS AND THUNDERSTORMS
                      LIKELY IN THE AFTERNOON. CHANCE OF WETTING
                      RAIN 60 PERCENT...WITH AMOUNTS OF 0.25 TO
                      0.50 INCHES MOST LIKELY.
MAX TEMPERATURE.......77-80 NEAR 8000 FEET...66-69 ALONG RIDGELINES.
MIN HUMIDITY..........30-33 PERCENT PERCENT NEAR 8000 FEET...42-45
                      PERCENT ALONG RIDGELINES.
WIND (20 FT)..........SOUTHWEST/UPSLOPE 6-12 MPH. RIDGELINE WINDS
                      SOUTHWEST 15-20 MPH WITH GUSTS NEAR 30 MPH.

.OUTLOOK FOR THURSDAY...
LAL...................5.
HAINES INDEX..........3 ..VERY LOW.
CLEARING INDEX........1000+.
SKY/WEATHER...........MOSTLY CLOUDY (70-80 PERCENT CLOUD COVER)
                      WITH SHOWERS AND THUNDERSTORMS LIKELY. CHANCE
                      OF WETTING RAIN 50 PERCENT WITH 0.15 TO 0.25
                      INCHES MOST LIKELY.
MAX TEMPERATURE.......75-78 NEAR 8000 FEET...64-67 ALONG RIDGELINES.
MIN HUMIDITY..........37-40 PERCENT PERCENT NEAR 8000 FEET...50-53
                      PERCENT ALONG RIDGELINES.
WIND (20 FT)..........SOUTHWEST/UPSLOPE 6-12 MPH. RIDGELINE WINDS
                      WEST 8-15 MPH WITH GUSTS NEAR 25 MPH.


FORECASTER...SEAMAN
REQUESTED BY...GSORENSON
REASON FOR REQUEST...WILDFIRE
.TAG 20100817.TWITC.01/SLC

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