FNUS75 KRIW 220832 FWSRIW SPOT FORECAST FOR ANTELOPE...NPS YNP NATIONAL WEATHER SERVICE RIVERTON WY 232 AM MDT WED SEP 22 2010 FORECAST IS BASED ON REQUEST TIME OF 2038 MDT ON SEPTEMBER 21. IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE. .DISCUSSION... A TROUGH WILL APPROACH WESTERN WYOMING TODAY AND MOVE ACROSS TONIGHT. SOUTH TO SOUTHWEST WINDS ARE EXPECTED THROUGH MID AFTERNOON...BEFORE A COLD FRONT MOVES THROUGH. THE WINDS WILL SHIFT TO THE NORTHWEST TO NORTH. RH'S WILL BOTTOM OUT IN MID 20S...BEFORE REBOUNDING BEHIND THE FRONT. GOOD RECOVERIES ARE EXPECTED OVERNIGHT WITH SOME LOW CLOUDS POSSIBLE. THERE IS A SLIGHT CHANCE FOR A SHOWER OR THUNDERSTORM THIS AFTERNOON AND EVENING. ZONAL FLOW BUILDS IN FOR THURSDAY...WITH GUSTY SOUTHWEST WINDS AND LOWER RH'S RETURNING. ...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS... ...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT... FORECASTER...T.BAKER .TODAY... SKY/WEATHER.........PARTLY CLOUDY (45-55 PERCENT) THEN BECOMING MOSTLY CLOUDY (60-70 PERCENT). ISOLATED RAIN SHOWERS AND ISOLATED THUNDERSTORMS IN THE AFTERNOON. MAX TEMPERATURE.....70-73. MIN HUMIDITY........23-26 PERCENT. 20 FOOT WINDS.......SOUTH 5-10 MPH BECOMING SOUTHWEST AROUND 10-15 WITH GUSTS TO 25 MPH AFTER 1100. SHIFTING TO THE NORTHWEST TO NORTH AROUND 1500 AT 5 TO 10 MPH GUSTS TO 15 MPH. GUSTY AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS. RIDGE TOP WINDS.....SOUTHWEST 10 TO 15 MPH GUSTS TO 30 MPH...SHIFTING NORTHWEST AROUND 10 MPH AROUND 1600. LAL.................1 UNTIL 1200...THEN 2. CHC OF WETTING RAIN.3 PERCENT. HAINES INDEX........5 OR MODERATE POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......2000 FT AGL INCREASING TO 7000 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....SOUTHWEST 20 MPH...SHIFTING NORTHWEST AROUND 1500. SMOKE DISPERSAL.....FAIR (40000 KNOT-FT) INCREASING TO VERY GOOD (140000 KNOT-FT) IN THE AFTERNOON. .TONIGHT... SKY/WEATHER.........MOSTLY CLOUDY (65-75 PERCENT). ISOLATED RAIN SHOWERS AND ISOLATED THUNDERSTORMS IN THE EVENING...THEN CHANCE OF RAIN AFTER MIDNIGHT. MIN TEMPERATURE.....AROUND 35. MAX HUMIDITY........93-96 PERCENT. 20 FOOT WINDS.......NORTH AROUND 5-10 MPH WITH GUSTS TO AROUND 15 MPH. GUSTY AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS. RIDGE TOP WINDS.....NORTHWEST TO NORTH 15 MPH. LAL.................2 UNTIL 2400...THEN 1. CHC OF WETTING RAIN.5 PERCENT. HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......5000 FT AGL DECREASING TO 1000 FT AGL AFTER MIDNIGHT. TRANSPORT WINDS.....NORTHWEST TO NORTH AROUND 15 MPH. SMOKE DISPERSAL.....GOOD (75000 KNOT-FT) DECREASING TO POOR (15000 KNOT-FT) AFTER MIDNIGHT. .THURSDAY... SKY/WEATHER.........MOSTLY CLOUDY (60-70 PERCENT). ISOLATED RAIN SHOWERS IN THE MORNING. THEN DECREASING CLOUDS. MAX TEMPERATURE.....62-65. MIN HUMIDITY........25-30 PERCENT. 20 FOOT WINDS.......VARIABLE 3-6 MPH BECOMING SOUTHWEST AROUND 5-10 MPH AND GUSTY LATE IN THE AFTERNOON. RIDGE TOP WINDS.....SOUTHWEST 10 TO 15 MPH INCREASING TO AROUND 20 MPH LATE IN THE AFTERNOON. LAL.................1. CHC OF WETTING RAIN.LESS THAN 5 PERCENT. HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME DOMINATED FIRE GROWTH. MIXING HEIGHT.......1500 FT AGL INCREASING TO 6000 FT AGL IN THE AFTERNOON. TRANSPORT WINDS.....SOUTHWEST 20 MPH. SMOKE DISPERSAL.....POOR (30000 KNOT-FT) INCREASING TO VERY GOOD (120000 KNOT-FT) IN THE AFTERNOON. .FORECAST DAYS 3 THROUGH 5... .THURSDAY NIGHT...PARTLY CLOUDY. LOWS IN THE LOWER 30S. WINDS GENERALLY LESS THAN 10 MPH. .FRIDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS. LOWS IN THE LOWER 30S. HIGHS IN THE UPPER 60S. WINDS GENERALLY LESS THAN 10 MPH. .SATURDAY...MOSTLY CLEAR. LOWS IN THE MID 30S. HIGHS IN THE LOWER 70S. WINDS GENERALLY LESS THAN 10 MPH. .SUNDAY...MOSTLY CLEAR. LOWS IN THE MID 30S. HIGHS IN THE LOWER 70S. WINDS GENERALLY LESS THAN 10 MPH. $$ FORECASTER...T.BAKER REQUESTED BY...LAURA DOOLEY REASON FOR REQUEST...WILDFIRE .TAG 20100921.ANTEL.02/RIW