FNUS75 KRIW 171906 FWSRIW SPOT FORECAST FOR BUTTE CREEK...USFS BTF NATIONAL WEATHER SERVICE RIVERTON WY 106 PM MDT FRI AUG 17 2012 FORECAST IS BASED ON IGNITION TIME OF 1225 MDT ON AUGUST 17. IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE. .DISCUSSION...NORTHWEST FLOW WILL CONTINUE TODAY. IT WILL BE BREEZY AT TIMES WHEN THE WINDS ALOFT MIX DOWN TO THE SURFACE THIS AFTERNOON AS A WEAK UPPER LEVEL DISTURBANCE APPROACHES THE AREA. OTHERWISE...A RIDGE OF HIGH PRESSURE BUILDS OVER WESTERN WYOMING ON SATURDAY AND SUNDAY. TODAYS HIGH TEMPERATURES WILL BE ABOUT THE SAME AS YESTERDAY. MINIMUM RELATIVE HUMIDITIES SHOULD RANGE FROM 15 TO 25 PERCENT THROUGH THE WEEKEND. THERE WILL BE A CHANCE OF THUNDERSTORMS ON SUNDAY AS AN UPPER LEVEL DISTURBANCE APPROACHES...HOWEVER THERE SHOULD BE ADEQUATE MOISTURE TO SUPPORT WET THUNDERSTORMS. GIVEN THE DRYNESS OF THE FUELS...THIS SITUATION WILL BE WATCHED CLOSELY BUT IT DOES NOT APPEAR TO BE HIGH IMPACT AT THIS TIME DUE TO THE LIMITED INSTABILITY AND ADEQUATE MOISTURE AT ALL LEVELS EXPECTED WITH THIS FEATURE. ...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS... ...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT... FORECASTER...LIPSON .TODAY... SKY/WEATHER.........MOSTLY SUNNY (10-20 PERCENT) THEN BECOMING PARTLY CLOUDY (35-45 PERCENT). AREAS OF SMOKE. MAX TEMPERATURE.....71. MIN HUMIDITY........19 PERCENT. 20 FOOT WINDS.......WEST SOUTHWEST 10 TO 15 MPH. AFTER 1500 WINDS FLUCTUATING BETWEEN WEST AND NORTH AT 5 TO 15 MPH. AFTER 1800 NORTH 10 TO 15 MPH. RIDGE TOP WINDS.....NORTHWEST 5 TO 10 MPH. LAL.................1. CHC OF WETTING RAIN.ZERO PERCENT. HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......2700-3700 FT AGL INCREASING TO 7000-8000 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....NORTHWEST 16 TO 18 MPH. SMOKE DISPERSAL.....FAIR (44900 KNOT-FT) INCREASING TO VERY GOOD (117400 KNOT-FT) IN THE AFTERNOON. .TONIGHT... SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT). AREAS OF SMOKE. MIN TEMPERATURE.....41-44. MAX HUMIDITY........58-61 PERCENT. 20 FOOT WINDS.......NORTH 7 TO 10 MPH BECOMING DOWNSLOPE/DOWNVALLEY 4-7 MPH AFTER MIDNIGHT. RIDGE TOP WINDS.....NORTHWEST AROUND 10 MPH SHIFTING TO THE EAST LATE IN THE EVENING...THEN BECOMING LIGHT AND VARIABLE AFTER MIDNIGHT BECOMING SOUTHWEST AROUND 5 MPH EARLY IN THE MORNING. LAL.................1. CHC OF WETTING RAIN.ZERO PERCENT. HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......5100-6100 FT AGL DECREASING TO 900-1900 FT AGL AFTER MIDNIGHT. TRANSPORT WINDS.....NORTHWEST 14 TO 20 MPH BECOMING NORTH AROUND 7 MPH AFTER MIDNIGHT. SMOKE DISPERSAL.....GOOD (84300 KNOT-FT) DECREASING TO POOR (10700 KNOT-FT) AFTER MIDNIGHT. .SATURDAY... SKY/WEATHER.........MOSTLY SUNNY (15-25 PERCENT). AREAS OF SMOKE. MAX TEMPERATURE.....71. MIN HUMIDITY........16 PERCENT. 20 FOOT WINDS.......UPSLOPE/UPVALLEY 5-9 MPH. RIDGE TOP WINDS.....WEST AROUND 5 MPH SHIFTING TO THE NORTHWEST IN THE AFTERNOON. LAL.................1. CHC OF WETTING RAIN.ZERO PERCENT. HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......2400-3400 FT AGL INCREASING TO 6200-7200 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....NORTHWEST 7 TO 9 MPH. SMOKE DISPERSAL.....POOR TO FAIR (18100-49200 KNOT-FT). .FORECAST DAYS 3 THROUGH 5... .SATURDAY NIGHT...MOSTLY CLEAR. AREAS OF SMOKE. LOWS IN THE LOWER 40S. WINDS GENERALLY LESS THAN 10 MPH. .SUNDAY...PARTLY CLOUDY WITH ISOLATED SHOWERS AND THUNDERSTORMS. LOWS IN THE LOWER 40S. HIGHS IN THE UPPER 60S. WINDS GENERALLY LESS THAN 10 MPH. .MONDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS IN THE MID 40S. HIGHS IN THE UPPER 60S. WINDS GENERALLY LESS THAN 10 MPH. .TUESDAY...MOSTLY CLEAR. SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS IN THE LOWER 40S. HIGHS IN THE UPPER 60S. WINDS GENERALLY LESS THAN 10 MPH. $$ FORECASTER...LIPSON REQUESTED BY...USFS REASON FOR REQUEST...PRESCRIBED .TAG 20120817.BUTTE.01/RIW