FNUS75 KRIW 230910 FWSRIW SPOT FORECAST FOR CHALL CREEK FIRE...USFS BTF NATIONAL WEATHER SERVICE RIVERTON WY 310 AM MDT SUN SEP 23 2012 FORECAST IS BASED ON REQUEST TIME OF 2215 MDT ON SEPTEMBER 22. IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE. .DISCUSSION... THE PERSISTENT WARM AND VERY DRY PATTERN IS COMING TO AN END AS A WEAK STORM SYSTEM OVER THE PACIFIC NORTHWEST TODAY SLOWLY PUSHES INTO THE NORTHERN GREAT BASIN MONDAY...AND THEN ACROSS THE CENTRAL AND SOUTHERN ROCKIES ON TUESDAY. THERE COULD BE AN ISOLATED SHOWER OR THUNDERSTORM THIS AFTERNOON INTO TONIGHT...BUT THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE MONDAY AND TUESDAY. THIS SYSTEM IS RELATIVELY WARM...WITH THE PRECIPITATION REMAINING ONLY RAIN ON THE WILDFIRE SITE. WINDS WILL BE RELATIVELY LIGHT OVER THE NEXT COUPLE OF DAYS...EXCEPT BECOMING PREDOMINATELY DOMINATED BY SHOWER AND THUNDERSTORM ACTIVITY ON MONDAY. ...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS... ...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT... FORECASTER...MURRELL .TODAY... SKY/WEATHER.........PARTLY CLOUDY (55 PERCENT) IN THE MORNING. MOSTLY CLOUDY (75 PERCENT) WITH VERY ISOLATED SHOWERS AND THUNDERSTORMS IN THE AFTERNOON. MAX TEMPERATURE.....70. MIN HUMIDITY........15-20 PERCENT. 20 FOOT WINDS.......BECOMING UPSLOPE/UPVALLEY OR SOUTH TO SOUTHEAST 4-8 MPH BY AROUND 10 AM. GUSTS TO 15 MPH IN THE AFTERNOON. GUSTIER AND ERRATIC WINDS EXPECTED NEAR ANY THUNDERSTORMS IN THE AFTERNOON. RIDGE TOP WINDS.....SOUTH TO SOUTHWEST 5-10 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.......7500 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....SOUTH 5-10 MPH...BECOMING SOUTHWEST 5-10 MPH IN THE AFTERNOON. SMOKE DISPERSAL.....FAIR TO GOOD IN THE AFTERNOON. .TONIGHT... SKY/WEATHER.........MOSTLY CLOUDY (75 PERCENT). ISOLATED SHOWERS THROUGH THE NIGHT. AN ISOLATED THUNDERSTORM POSSIBLE THROUGH 9 PM. MIN TEMPERATURE.....40-45. MAX HUMIDITY........70-75 PERCENT. 20 FOOT WINDS.......DOWNSLOPE/DOWNVALLEY 4-7 MPH. GUSTY AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS IN THE EVENING. RIDGE TOP WINDS.....SOUTH 5-10 MPH LAL.................2 UNTIL 9 PM...THEN 1. CHC OF WETTING RAIN.5 PERCENT. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......DECREASING TO 1200 FT AGL BY 9 PM. TRANSPORT WINDS.....SOUTH 5-10 MPH. SMOKE DISPERSAL.....POOR. .MONDAY... SKY/WEATHER.........CLOUDY (85-100 PERCENT). SCATTERED RAIN SHOWERS THROUGH THE DAY. ISOLATED THUNDERSTORMS IN THE AFTERNOON. MAX TEMPERATURE.....AROUND 60. MIN HUMIDITY........45-50 PERCENT. 20 FOOT WINDS.......LIGHT AND VARIABLE 3-6 MPH...BECOMING NORTHWEST 5-10 MPH IN THE AFTERNOON. GUSTS AROUND 15 MPH IN THE AFTERNOON. GUSTIER AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS IN THE AFTERNOON. RIDGE TOP WINDS.....VARIABLE 5-10 MPH...BECOMING NORTHWEST AROUND 10 MPH AROUND 2 PM. LAL.................1 UNTIL NOON...THEN 2. CHC OF WETTING RAIN.20 PERCENT. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......4500 FT AGL. TRANSPORT WINDS.....VARIABLE 5-10 MPH...BECOMING NORTHWEST AROUND 10 MPH AROUND 2 PM. SMOKE DISPERSAL.....POOR. .FORECAST DAYS 3 THROUGH 5... .MONDAY NIGHT...MOSTLY CLOUDY. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS IN THE EVENING...THEN ISOLATED SHOWERS AFTER MIDNIGHT. LOWS AROUND 40. WINDS GENERALLY LESS THAN 10 MPH. .TUESDAY...MOSTLY CLOUDY. SCATTERED SHOWERS. LOWS IN THE LOWER 40S. HIGHS IN THE MID 50S. WINDS GENERALLY LESS THAN 10 MPH. .WEDNESDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS IN THE MID 40S. HIGHS IN THE UPPER 50S. WINDS GENERALLY LESS THAN 10 MPH. .THURSDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS. LOWS IN THE LOWER 40S. HIGHS IN THE LOWER 60S. WINDS GENERALLY LESS THAN 10 MPH. $$ FORECASTER...MURRELL REQUESTED BY...ROD DYKEHOUSE REASON FOR REQUEST...WILDFIRE .TAG 20120922.CHALL.01/RIW