FNUS75 KRIW 171444
FWSRIW

SPOT FORECAST FOR LOWER GROS VENTRE...USFS BTF
NATIONAL WEATHER SERVICE RIVERTON WY
844 AM MDT THU SEP 17 2009

FORECAST IS BASED ON IGNITION TIME OF 0825 MDT ON SEPTEMBER 17.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...
A STRONG UPPER LEVEL HIGH CENTERED OVER THE WYOMING-MONTANA-SOUTH
DAKOTA TRIPLE POINT THIS MORNING WILL CONTINUE TO KEEP MAINLY DRY AND
WARM CONDITIONS OVER THE BURN AREA THROUGH FRIDAY. LIGHT UPSLOPE
FLOW WILL DOMINATE THE WIND PATTERN THROUGH FRIDAY AS WELL. SOUTHWEST
WIND WILL BEGIN TO INCREASE SATURDAY AFTERNOON...AHEAD OF AN
APPROACHING PACIFIC TROUGH.

...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS...
...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT...

FORECASTER...CHURCH

.TODAY...
SKY/WEATHER.........MOSTLY SUNNY (5-15 PERCENT) THEN BECOMING
                    PARTLY CLOUDY (35-45 PERCENT). SLIGHT CHANCE FOR
                    A HIGH BASED ISOLATED SHOWER OR THUNDERSTORM IN
                    THE AFTERNOON.
MAX TEMPERATURE.....66-69.
MIN HUMIDITY........24-28 PERCENT.
20 FOOT WINDS.......UPSLOPE (W/SW) 4-9 MPH. GUSTY AND ERRATIC
                    WINDS EXPECTED NEAR THUNDERSTORMS IN THE
                    AFTERNOON.
RIDGE TOP WINDS.....SOUTHWEST 3-6 MPH...BECOMING WEST-NORTHWEST 4-7 MPH
                    IN THE AFTERNOON.
LAL.................1 UNTIL 1200...THEN 2.
CHC OF WETTING RAIN.LESS THAN 5 PERCENT.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
MIXING HEIGHT.......4800 FT AGL INCREASING TO 9100 FT AGL IN THE
                    AFTERNOON.
TRANSPORT WINDS.....SOUTHWEST 6 TO 10 MPH.
SMOKE DISPERSAL..... GOOD (44900-66600 KNOT-FT).

.TONIGHT...
SKY/WEATHER.........PARTLY CLOUDY (30-40 PERCENT). ISOLATED SHOWERS
                    AND THUNDERSTORMS EARLY IN THE EVENING.
MIN TEMPERATURE.....48-51.
MAX HUMIDITY........48-53 PERCENT.
20 FOOT WINDS.......DOWNSLOPE 4-7 MPH. GUSTY AND ERRATIC
                    WINDS EXPECTED NEAR THUNDERSTORMS EARLY IN THE
                    EVENING.
RIDGE TOP WINDS.....LIGHT AND VARIABLE 2 TO 5 MPH.
LAL.................2 UNTIL 2100...THEN 1.
CHC OF WETTING RAIN.LESS THAN 5 PERCENT.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
MIXING HEIGHT.......4900 FT AGL DECREASING TO 700 FT AGL AFTER
                    MIDNIGHT.
TRANSPORT WINDS.....SOUTHWEST 5 MPH.
SMOKE DISPERSAL.....POOR (4400-25100 KNOT-FT).

.FRIDAY...
SKY/WEATHER.........MOSTLY SUNNY (15-25 PERCENT) THEN BECOMING
                    PARTLY CLOUDY (35-45 PERCENT). ISOLATED SHOWERS
                    AND THUNDERSTORMS IN THE AFTERNOON.
MAX TEMPERATURE.....67-71.
MIN HUMIDITY........27-31 PERCENT.
20 FOOT WINDS.......UPSLOPE 3-6 MPH. GUSTY AND ERRATIC
                    WINDS EXPECTED NEAR THUNDERSTORMS IN THE
                    AFTERNOON.
RIDGE TOP WINDS.....WEST AROUND 5 MPH.
LAL.................1 UNTIL 1200...THEN 2.
CHC OF WETTING RAIN.LESS THAN 5 PERCENT.
HAINES INDEX........5 OR MODERATE POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
MIXING HEIGHT.......5300 FT AGL INCREASING TO 10000 FT AGL IN THE
                    AFTERNOON.
TRANSPORT WINDS.....WEST AROUND 5 MPH.
SMOKE DISPERSAL.....FAIR (33800-46100 KNOT-FT).

.FORECAST DAYS 3 THROUGH 5...
.FRIDAY NIGHT...PARTLY CLOUDY. LOWS IN THE MID 40S. WINDS
GENERALLY LESS THAN 10 MPH.
.SATURDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS. LOWS IN THE UPPER 40S. HIGHS IN THE MID 60S. WEST WIND
10 TO 20 MPH.
.SUNDAY...MOSTLY CLOUDY. SLIGHT CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS. LOWS IN THE MID 30S. HIGHS IN THE UPPER 50S. WEST WIND
15 TO 20 MPH.
.MONDAY...MOSTLY CLEAR. COOLER. LOWS IN THE MID 30S. HIGHS IN THE MID
50S. NORTHWEST WIND 10 TO 20 MPH.

$$

FORECASTER...CHURCH
REQUESTED BY...MCFARLAND
REASON FOR REQUEST...PRESCRIBED
.TAG 20090917.LOWER.01/RIW