FNUS75 KRIW 040842 FWSRIW SPOT FORECAST FOR UPPER CLARKS FORK RX...USFS SHF NATIONAL WEATHER SERVICE RIVERTON WY 242 AM MDT WED APR 4 2012 FORECAST IS BASED ON IGNITION TIME OF 1200 MDT ON APRIL 04. IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE. .DISCUSSION...AN UPPER TROUGH OF LOW PRESSURE ALONG THE NORTHWEST COAST WILL EJECT A SERIES OF DISTURBANCES NORTHEAST ACROSS THE INTERMOUNTAIN WEST TODAY THROUGH FRIDAY. THE FIRST IN THIS SERIES WILL PUSH A COLD FRONT ACROSS EASTERN IDAHO THIS AFTERNOON...AND INTO NORTHWEST WYOMING LATE AFTERNOON/EARLY EVENING. RIDGE TOP SOUTHWEST WIND WILL INCREASE THIS AFTERNOON AHEAD OF THE FRONT WITH WNW WINDS FUNNELED THROUGH THE VALLEY ONCE AGAIN. TEMPERATURES WILL TREND SLIGHTLY WARMER AND RELATIVE HUMIDITY HIGHER TODAY. MOST SHOWER ACTIVITY WILL STAY WEST OF THE BURN SITE WITH SOME PASSING SHOWERS MAINLY AFTER 1600L. THE COLD FRONT WILL PUSH SOUTH...EAST OF THE DIVIDE EARLY THURSDAY MORNING...WITH A MOIST UPSLOPE SE FLOW DEVELOPING WITH A BETTER CHANCE OF ACCUMULATING SNOW ALONG WITH MUCH COOLER TEMPERATURES...HIGHER RELATIVE HUMIDITY THROUGH THE DAY. ...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS... ...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT... FORECASTER...MEUNIER .TODAY... SKY/WEATHER.........PARTLY CLOUDY (50-60 PERCENT)...BECOMING MOSTLY CLOUDY (70-80 PERCENT) WITH ISOLATED RAIN SHOWERS AFTER 1600L. MAX TEMPERATURE.....54-57. MIN HUMIDITY........26-29 PERCENT. 20 FOOT WINDS.......WEST NORTHWEST 5 TO 10 MPH IN THE MORNING...INCREASING TO 10 TO 15 MPH WITH GUSTS 20 TO 25 MPH BETWEEN 1300L AND 1500L. RIDGE TOP WINDS.....SOUTHWEST 10 TO 15 MPH. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......2100-3100 FT AGL INCREASING TO 4800-5800 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....SOUTHWEST 15 TO 20 MPH. SMOKE DISPERSAL.....POOR (31000 KNOT-FT) INCREASING TO GOOD (87100 KNOT-FT) IN THE AFTERNOON. .TONIGHT... SKY/WEATHER.........MOSTLY CLOUDY (70-80 PERCENT). SLIGHT CHANCE OF RAIN IN THE EVENING...THEN SLIGHT CHANCE OF SNOW AFTER MIDNIGHT. MIN TEMPERATURE.....24-27. MAX HUMIDITY........80-83 PERCENT. 20 FOOT WINDS.......WEST NORTHWEST 10 MPH WITH GUSTS TO AROUND 15 MPH IN THE EVENING...BECOMING SOUTHEAST 5 TO 9 MPH AFTER MIDNIGHT. RIDGE TOP WINDS.....SOUTHWEST 10 TO 15 MPH...BECOMING SOUTH SOUTHEAST AROUND 10 MPH AFTER MIDNIGHT. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......4300-5300 FT AGL DECREASING TO 1900-2900 FT AGL AFTER MIDNIGHT. TRANSPORT WINDS.....SOUTHWEST 15 TO 20 MPH DECREASING TO AROUND 10 MPH AFTER MIDNIGHT...AND BECOMING SOUTHEAST 5 TO 10 MPH AFTER 0200L . SMOKE DISPERSAL.....GOOD (81800 KNOT-FT) DECREASING TO POOR (23000 KNOT-FT) AFTER MIDNIGHT. .THURSDAY... SKY/WEATHER.........CLOUDY (85-95 PERCENT). CHANCE OF SNOW IN THE MORNING...THEN NUMEROUS RAIN SHOWERS AND SNOW SHOWERS IN THE AFTERNOON. MAX TEMPERATURE.....AROUND 40. MIN HUMIDITY........62-65 PERCENT. 20 FOOT WINDS.......UPSLOPE/UPVALLEY OR SOUTHEAST 5-9 MPH. RIDGE TOP WINDS.....SOUTHEAST AROUND 10 MPH. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......2600-3600 FT AGL. TRANSPORT WINDS.....EAST SOUTHEAST AROUND 10 MPH. SMOKE DISPERSAL.....POOR (12700-21700 KNOT-FT). .FORECAST DAYS 3 THROUGH 5... .THURSDAY NIGHT...CLOUDY. SCATTERED SNOW SHOWERS IN THE EVENING... THEN CHANCE OF SNOW AFTER MIDNIGHT. LOWS IN THE MID 20S. WINDS GENERALLY LESS THAN 10 MPH. .FRIDAY...CLOUDY WITH CHANCE OF SNOW. LOWS AROUND 17. HIGHS IN THE LOWER 30S. WINDS GENERALLY LESS THAN 10 MPH. .SATURDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SNOW SHOWERS. LOWS IN THE LOWER 20S. HIGHS IN THE MID 30S. WINDS GENERALLY LESS THAN 10 MPH. .SUNDAY...NOT AS COOL. PARTLY CLOUDY. LOWS IN THE UPPER 20S. HIGHS IN THE UPPER 40S. WINDS GENERALLY LESS THAN 10 MPH. $$ FORECASTER...MEUNIER REQUESTED BY...CLINT DAWSON REASON FOR REQUEST...PRESCRIBED .TAG 20120404.UPPER.01/RIW