FNUS75 KTFX 201632
FWSTFX

SPOT FORECAST FOR DEEP CREEK RX...HNF
NATIONAL WEATHER SERVICE GREAT FALLS MT
1032 AM MDT TUE APR 20 2010

FORECAST IS BASED ON IGNITION TIME OF 1010 MDT ON APRIL 20.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...

AN AREA OF LOW PRESSURE TRACKING INTO THE GREAT BASIN TONIGHT
THROUGH WEDNESDAY WILL MAINTAIN WINDS FROM THE EAST TO SOUTHEAST
ACROSS MUCH OF CENTRAL MONTANA THROUGH WEDNESDAY. THE AIRMASS WILL
BECOME SOMEWHAT UNSTABLE LATER THIS AFTERNOON...ALLOWING FOR THE
DEVELOPMENT OF SOME MODERATE CUMULUS CLOUDS WHICH MAY PRODUCE A
FEW SPRINKLES AND ERRATIC DOWNDRAFT GUSTS LATE THIS AFTERNOON AND
EVENING. OTHERWISE...WINDS WILL MAINLY BE LIGHT AND DRIVEN BY THE
TERRAIN AT LOWER TO MID SLOPES WITH SOUTHEAST TO EAST WINDS ACROSS
THE RIDGETOPS AND THROUGH DEEP CREEK CANYON. ON WEDNESDAY
INSTABILITY WILL FURTHER INCREASE DURING THE AFTERNOON AND EARLY
EVENING FOR A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS...HOWEVER
AFTERNOON RELATIVE HUMIDITIES SHOULD STILL DROP BELOW 30% BEFORE
THE CLOUD-COVER INCREASES. WINDS WILL CONTINUE TO BE DRIVEN BY
TERRAIN AND SLOPE-HEATING AT MID TO LOWER SLOPES WITH WITH AN
EASTERLY FLOW THROUGH MUCH OF DEEP CREEK CANYON. UPPER LEVEL RIDGE
TOP WINDS WILL BE SOMEWHAT BREEZY AND FROM THE EAST TO SOUTHEAST.
HOENISCH


.REST OF TODAY...

SKY/WEATHER.........MOSTLY SUNNY THROUGH EARLY AFTERNOON WITH
                    CUMULUS CLOUDS BUILDING IN THE AFTERNOON.
                    AN ISOLATED SPRINKLE IN POSSIBLE IN THE LATE
                    AFTERNOON.
CWR.................5 PERCENT.
MAX TEMPERATURE.....66-71.
MIN HUMIDITY........22-27 PERCENT.
WIND (20 FT)........UPLSOPE/UPVALLEY WINDS 3-6 MPH WITH EAST WINDS
                    5-10 MPH THROUGH DEEP CREEK CANYON.
 UPR SLP/RIDGETOP...SOUTHEAST WINDS 10-15 MPH.
MIXING HEIGHT.......5000 FT AGL.
MIXING WINDS........SOUTHEAST 10-15 MPH.

.TONIGHT...

SKY/WEATHER.........PARTLY CLOUDY. AN ISOLATED SPRINKLE POSSIBLE
                    EARLY IN THE EVENING.
CWR.................5 PERCENT.
MIN TEMPERATURE.....35-40.
MAX HUMIDITY........76-81 PERCENT.
WIND (20 FT)........BECOMING DOWNSLOPE/DOWN-VALLEY 3-6 MPH AFTER
                    SUNSET.
 UPR SLP/RIDGETOP...EAST WINDS 10-15 MPH
MIXING HEIGHT.......LOWERING TO LESS THAN 1000 FT AGL.
MIXING WINDS........EAST AROUND 10 MPH.

.WEDNESDAY...

SKY/WEATHER.........PARTLY SUNNY. SLIGHT CHANCE OF A SHOWER OR
                    THUNDERSTORM IN THE AFTERNOON AND EVENING.
CWR.................10 PERCENT.
MAX TEMPERATURE.....64-69.
MIN HUMIDITY........23-28 PERCENT.
WIND (20 FT)........UPSLOPE/UPVALLEY WINDS 3 TO 6 MPH AT
                    MID-SLOPE LOCATIONS WITH EAST WINDS 6-12 MPH
                    IN EXPOSED LOCATIONS AND THROUGH DEEP CREEK
                    CANYON.
 UPR SLP/RIDGETOP...EAST WINDS 10-15 MPH WITH GUSTS TO 20 MPH.
MIXING HEIGHT.......5000 FT AGL.
MIXING WINDS........EAST AROUND 10-15 MPH.


$$
FORECASTER...HOENISCH
REQUESTED BY...HDC
TYPE OF REQUEST...PRESCRIBED
.TAG 20100420.DEEPC.01/TFX