299  
FNUS75 KRIW 282109  
FWSRIW  
 
SPOT FORECAST FOR WILLOW CREEK FIRE...BLM  
NATIONAL WEATHER SERVICE RIVERTON WY  
309 PM MDT THU AUG 28 2025  
 
FORECAST IS BASED ON FORECAST START TIME OF 0600 MDT ON AUGUST 29.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE  
   
DISCUSSION  
 
DRIER CONDITIONS ARE EXPECTED ACROSS THE AREA TODAY WITH A VERY  
ISOLATED SHOWER OR THUNDERSTORM POSSIBLE AS CHANCES REMAIN AROUND  
10%. MOISTURE WILL START TO DIMINISH OVER THE REGION BUT MIN RH IS  
EXPECTED TO REMAIN ABOVE CRITICAL VALUES. FORECASTED PERCENTAGES  
RANGE FROM 30 TO 45% FOR MUCH OF THE AREA. WINDS INCREASE IN THE  
AFTERNOON FROM THE NORTHWEST AT AROUND 10 MPH WITH PERIODIC GUSTS  
NEAR 20 MPH. AN BRIEF ISOLATED GUST NEAR 30 MPH CANNOT BE RULED OUT  
WITH ANY NEARBY SHOWERS OR THUNDERSTORMS. SKIES ARE FORECAST TO  
GRADUALLY CLEAR OUT THROUGH THE MORNING LEADING TO PARTLY TO MOSTLY  
CLEAR SKIES. PRECIPITATION CHANCES DIMINISH FOR SATURDAY WITH AT  
BEST A VERY ISOLATED SHOWER OR THUNDERSTORM POSSIBLE WITH CHANCES  
AROUND 5 TO 10%. DRY AND WARMER CONDITIONS LOOK LIKELY TO REDEVELOP  
ACROSS THE AREA FOR SUNDAY INTO THE FIRST HALF OF NEXT WEEK.  
FORTUNATELY AT THIS TIME ANY CONCERNS FOR ELEVATED FIRE WEATHER  
CONDITIONS REMAINS LOW AS WINDS LOOK LIGHT AND MIN RH STAYS ABOVE  
CRITICAL VALUES.  
   
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS  
 
   
FRIDAY  
 
SKY/WEATHER.........SUNNY (10-20 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF PCPN......10 PERCENT.  
CHANCE OF THUNDER...6 PERCENT.  
MAX TEMPERATURE.....62-69.  
MIN HUMIDITY........35 PERCENT.  
WIND (20 FT)........LIGHT WINDS UNTIL 1200, THEN NORTH 7 TO 9 MPH  
WITH GUSTS TO AROUND 14 MPH.  
RIDGETOP WIND.......LIGHT WINDS UNTIL 1000, THEN NORTHWEST 10 TO 15  
MPH.  
MIXING HEIGHT.......7000 FT AGL AFTER 1300.  
TRANSPORT WINDS.....WEST AROUND 7 MPH UNTIL 0700, THEN NORTH UNTIL  
0800, THEN NORTHWEST 7 TO 15 MPH.  
SMOKE DISPERSAL.....POOR UNTIL 1000. GOOD EARLY IN THE MORNING  
INCREASING TO VERY GOOD IN THE AFTERNOON AFTER  
1400.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........15 10 10 5 10 10 10 15 15 15 20 20  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 10  
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 10  
TEMP............47 49 52 54 57 60 62 64 65 66 65 64  
RH..............76 72 68 64 57 50 43 40 37 34 36 37  
20 FT WIND DIR..SE E E N NW NW N NW NW N N N  
20 FT WIND SPD..3 3 2 3 5 6 7 7 8 8 8 9  
20 FT WIND GUST.4 5 5 7 10 11 11 12 13 13 14  
RIDGE WIND DIR..SE E E N NW NW N NW NW N N N  
RIDGE WIND SPD..5 5 5 5 10 10 15 15 15 15 15 15  
MIX HGT (KFT)...0.1 0.1 0.1 0.5 2.0 4.0 5.5 6.5 6.5 7.0 7.0 6.5  
TRANSP WIND DIR.W N N NW NW NW NW NW NW NW NW N  
TRANSP WIND SPD.7 7 6 7 9 12 13 13 14 14 15 15  
SDSPL KT-FT/100012 12 8 13 33 66 84 95 101 114 111 109  
   
FRIDAY NIGHT  
 
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF PCPN......10 PERCENT.  
CHANCE OF THUNDER...7 PERCENT.  
MIN TEMPERATURE.....AROUND 47.  
MAX HUMIDITY........58-69 PERCENT.  
WIND (20 FT)........NORTH WINDS 7 TO 9 MPH WITH GUSTS TO AROUND 17  
MPH UNTIL 2100, THEN LIGHT.  
RIDGETOP WIND.......NORTH 10 TO 15 MPH UNTIL 0100, THEN NORTHEAST  
UNTIL 0300, THEN LIGHT.  
MIXING HEIGHT.......6000 FT AGL UNTIL 1900.  
TRANSPORT WINDS.....NORTH 7 TO 15 MPH.  
SMOKE DISPERSAL.....VERY GOOD EARLY IN THE EVENING DECREASING TO  
GOOD LATE IN THE NIGHT UNTIL 1900. POOR AFTER  
2000.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........25 25 25 25 30 25 15 15 15 15 15 10  
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 0 0 0 0 0 0  
CHC OF THDR (%).10 10 10 10 10 10 0 0 0 0 0 0  
TEMP............63 61 57 55 53 52 52 51 51 50 49 48  
RH..............39 43 49 51 54 57 59 61 62 62 63 63  
20 FT WIND DIR..N N N N N NE NE NE NE E E E  
20 FT WIND SPD..9 8 7 6 6 6 5 5 4 4 4 4  
20 FT WIND GUST.17 14 12 11 10 7 6 6 6 6 6 6  
RIDGE WIND DIR..N N N N N NE NE NE NE E E E  
RIDGE WIND SPD..15 15 15 10 10 10 10 10 10 5 5 5  
MIX HGT (KFT)...6.0 1.5 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1  
TRANSP WIND DIR.N N N N N N N N N N N NW  
TRANSP WIND SPD.15 14 13 12 10 9 8 8 8 7 7 7  
SDSPL KT-FT/1000102 44 14 15 13 12 10 10 10 10 10 10  
   
SATURDAY  
 
SKY/WEATHER.........SUNNY (5-15 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF PCPN......10 PERCENT.  
CHANCE OF THUNDER...6 PERCENT.  
MAX TEMPERATURE.....65-73.  
MIN HUMIDITY........30-36 PERCENT.  
WIND (20 FT)........LIGHT WINDS UNTIL 1200, THEN NORTHWEST 7 TO 9  
MPH WITH GUSTS TO AROUND 17 MPH.  
RIDGETOP WIND.......LIGHT WINDS UNTIL 1000, THEN NORTHWEST 10 TO 15  
MPH.  
MIXING HEIGHT.......8500 FT AGL AFTER 1200.  
TRANSPORT WINDS.....NORTHWEST 7 TO 15 MPH.  
SMOKE DISPERSAL.....POOR UNTIL 1000. GOOD EARLY IN THE MORNING  
INCREASING TO VERY GOOD IN THE AFTERNOON AFTER  
1200.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........10 5 5 5 5 5 5 10 10 10 10 10  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).0 0 0 0 0 0 10 10 10 10 10 10  
CHC OF THDR (%).0 0 0 0 0 0 10 10 10 10 10 10  
TEMP............48 50 52 55 58 61 64 66 66 66 67 66  
RH..............62 60 58 54 48 43 38 35 33 33 31 31  
20 FT WIND DIR..E NE N N N NW NW NW NW NW NW NW  
20 FT WIND SPD..4 4 4 4 5 6 7 8 8 8 9 9  
20 FT WIND GUST.6 6 6 6 7 10 12 14 14 16 17 17  
RIDGE WIND DIR..E NE N N N NW NW NW NW NW NW NW  
RIDGE WIND SPD..5 5 5 5 10 10 10 15 15 15 15 15  
MIX HGT (KFT)...0.1 0.1 0.1 0.5 2.5 4.5 7.0 7.5 8.0 8.5 8.0 7.0  
TRANSP WIND DIR.NW W NW NW NW NW NW NW NW NW NW NW  
TRANSP WIND SPD.7 7 7 7 8 10 13 14 14 14 15 15  
SDSPL KT-FT/100010 12 13 15 32 61 98 113 130 136 128 119  
   
FORECAST DAYS 3 THROUGH 5  
   
SUNDAY  
 
CLEAR. LOWS IN THE UPPER 40S. HIGHS IN THE LOWER 70S. LIGHT  
WINDS.    
LABOR DAY  
 
MOSTLY CLEAR. LOWS AROUND 50. HIGHS IN THE MID 70S. LIGHT WINDS.    
TUESDAY  
 
MOSTLY CLEAR. LOWS IN THE LOWER 50S. HIGHS IN THE MID 70S. LIGHT  
WINDS.  
 
 
FORECASTER...DZIEWALTOWSKI  
REQUESTED BY...DIONYSIUS NICOLAS - PLANS SECTION  
TYPE OF REQUEST...WILDFIRE  
.TAG 2520679.3/RIW  
.DELDT 08/28/25  
.FORMATTERVERSION 2.0.0  
.EMAIL DIONYSIUS-CAESAR_NICOLAS@FIRENET.GOV,DNICOLAS@BLM.GOV  
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