091  
FNUS75 KRIW 191602  
FWSRIW  
 
SPOT FORECAST FOR MARGES DELIGHT PILES...USFS  
NATIONAL WEATHER SERVICE RIVERTON WY  
902 AM MST WED NOV 19 2025  
 
FORECAST IS BASED ON IGNITION TIME OF 0900 MST ON NOVEMBER 20.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE  
   
DISCUSSION  
 
GENERALLY QUIET WEATHER EXPECTED THURSDAY. WIND WILL BE LIGHT, LESS  
THAN 10 MPH UPSLOPE/UPVALLEY. WINDS SHIFT TO DOWNSLOPE/DOWNVALLEY  
AROUND SUNSET, GENERALLY LESS THAN 5 MPH FROM SUNSET THROUGH THE REST  
OF THE NIGHT. WITH LIGHT WINDS, EXPECT SMOKE DISPERSAL TO BE POOR.  
IN TERMS OF PRECIPITATION, IT WILL BE MOSTLY CLOUDY THROUGH MUCH OF  
THE DAY, WITH A 20% CHANCE OF LIGHT SNOW SHOWERS AFTER 1100L.  
LITTLE TO NO ACCUMULATION IS EXPECTED WITH ANY SHOWERS. SNOW SHOWERS  
WOULD MOVE IN FROM THE EAST-SOUTHEAST AND GENERALLY MOVE FROM EAST  
TO WEST. ANY SHOWERS WOULD BE BRIEF WITH THE MAIN CONCERN BEING  
SLIGHTLY REDUCED VISIBILITY AT TIMES. SNOW SHOWER CHANCES DECREASE  
AFTER SUNSET BUT SLIGHT CHANCES ARE POSSIBLE OVERNIGHT.  
   
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS  
 
   
THURSDAY  
 
SKY/WEATHER.........MOSTLY CLOUDY (50-60 PERCENT). SLIGHT CHANCE OF  
SNOW SHOWERS AFTER 1100.  
CWR.................0 PERCENT.  
CHANCE OF PCPN......20 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
MAX TEMPERATURE.....AROUND 37.  
MIN HUMIDITY........72 PERCENT.  
WIND (20 FT)........LIGHT UPSLOPE/UPVALLEY WINDS AROUND 5 TO 8  
MPH.  
RIDGETOP WIND.......NORTHEAST AROUND 10 MPH UNTIL 1100, THEN EAST.  
MIXING HEIGHT.......2500 FT AGL UNTIL 1700, THEN 500 FT AGL.  
TRANSPORT WINDS.....EAST 8 TO 10 MPH.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MST) 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........55 55 55 55 60 65 60 55 50  
WEATHER COV..... SCH SCH SCH SCH SCH SCH  
WEATHER TYPE....SW SW SW SW SW SW SW SW  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).10 10 20 20 20 20 20 20 10  
CHC OF THDR (%).0 0 0 0 0 0 0 0 0  
TEMP............30 33 35 36 37 37 37 36 34  
RH..............88 83 81 77 74 72 72 73 75  
20 FT WIND DIR..N E E E E E E E NE  
20 FT WIND SPD..4 4 5 5 5 5 4 4 3  
20 FT WIND GUST.6 7 8 10 10 10 10 8 7  
RIDGE WIND DIR..N E E E E E E E NE  
RIDGE WIND SPD..10 10 10 10 10 10 10 10 10  
MIX HGT (KFT)...1.0 1.5 1.5 2.0 2.0 2.5 2.0 1.0 0.5  
TRANSP WIND DIR.E E SE SE SE SE E E E  
TRANSP WIND SPD.9 9 10 10 10 10 9 9 8  
SDSPL KT-FT/10007 10 15 17 19 21 14 10 4  
   
THURSDAY NIGHT  
 
SKY/WEATHER.........MOSTLY CLOUDY (50-60 PERCENT). OCCASIONAL  
LIGHT SNOW SHOWERS ARE POSSIBLE THROUGH  
THE NIGHT.  
CWR.................0 PERCENT.  
CHANCE OF PCPN......10 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
MIN TEMPERATURE.....AROUND 23.  
MAX HUMIDITY........83 PERCENT.  
WIND (20 FT)........LIGHT DOWNSLOPE/DOWNVALLEY WIND LESS THAN 5  
MPH.  
RIDGETOP WIND.......NORTH AROUND 10 MPH UNTIL 2400, THEN NORTHWEST.  
MIXING HEIGHT.......500 FT AGL.  
TRANSPORT WINDS.....EAST 8 TO 9 MPH UNTIL 2200, THEN SOUTH 9 TO 10  
MPH UNTIL 0400, THEN WEST AROUND 12 MPH.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MST) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........50 55 55 55 50 50 50 50 50 55 55 55  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).10 10 10 10 10 10 10 10 10 10 10 10  
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............32 30 29 28 28 28 28 27 27 26 25 25  
RH..............78 81 83 83 83 82 83 83 84 84 84 84  
20 FT WIND DIR..NE N N N NW NW NW NW NW NW NW NW  
20 FT WIND SPD..3 3 3 4 4 5 5 5 5 5 6 6  
20 FT WIND GUST.6 6 6 6 6 7 8 8 10 10 11 11  
RIDGE WIND DIR..NE N N N NW NW NW NW NW NW NW NW  
RIDGE WIND SPD..10 10 10 10 10 10 10 10 10 10 10 10  
MIX HGT (KFT)...0.5 0.5 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0  
TRANSP WIND DIR.E E E E SE S S S S S W W  
TRANSP WIND SPD.8 8 8 9 9 10 10 10 10 10 12 12  
SDSPL KT-FT/10005 5 5 6 6 7 7 7 8 7 8 8  
 
 
FORECASTER...HENSLEY  
REQUESTED BY...CODY NORTON  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2526388.0/RIW  
.DELDT 11/19/25  
.FORMATTERVERSION 2.0.0  
.EMAIL CODY.NORTON@USDA.GOV  
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