365  
FNUS75 KRIW 171139  
FWSRIW  
 
SPOT FORECAST FOR HORSE...USFS  
NATIONAL WEATHER SERVICE RIVERTON WY  
539 AM MDT THU JUL 17 2025  
 
FORECAST IS BASED ON FORECAST START TIME OF 0600 MDT ON JULY 17.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE  
   
DISCUSSION  
 
SLIGHTLY WARMER WITH MORE UNSTABLE CONDITIONS ARE FORECAST TODAY.  
WESTERLY WINDS INCREASE TO 15-20 MPH AFTER 1000L AND CONTINUE  
THROUGH 2000L. EXPECT GUSTS GENERALLY AROUND 25 MPH WITH OCCASIONAL  
GUSTS UP TO 30 MPH BETWEEN 1300L-1800L. MIXING AND SMOKE DISPERSAL  
WILL BE EXCELLENT BETWEEN 1300L-1800L. LITTLE TO NO PRECIPITATION  
CHANCES TODAY. RELATIVE HUMIDITY RECOVERY IS EXPECTED TO BE POOR  
TONIGHT. SIMILAR TEMPERATURES, SLIGHTLY HIGHER RELATIVE HUMIDITY  
VALUES, AND BREEZY WINDS ARE FORECAST ON FRIDAY WITH INCREASED  
PRECIPITATION CHANCES IN THE AFTERNOON.  
   
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS  
 
   
TODAY  
 
SKY/WEATHER.........SUNNY (0-10 PERCENT). AREAS OF SMOKE ARE  
POSSIBLE LATE IN THE MORNING THROUGH EARLY  
AFTERNOON.  
CWR.................0 PERCENT.  
CHANCE OF PCPN......0 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
MAX TEMPERATURE.....AROUND 73.  
MIN HUMIDITY........21 PERCENT.  
WIND (20 FT)........LIGHT WINDS UNTIL 0800, THEN WEST 7 TO 16 MPH  
WITH GUSTS TO AROUND 22 MPH.  
RIDGETOP WIND.......WEST 10 TO 15 MPH UNTIL 1000, THEN 20 TO 25  
MPH.  
MIXING HEIGHT.......500 FT AGL UNTIL 0900. 10500 FT AGL AFTER 1300.  
TRANSPORT WINDS.....WEST 12 TO 16 MPH UNTIL 1000, THEN 22 TO 28  
MPH.  
SMOKE DISPERSAL.....POOR UNTIL 0900. EXCELLENT AFTER 1300.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........5 5 0 0 0 0 0 0 5 5 5 5  
WEATHER COV..... ARS ARS  
WEATHER TYPE.... SMK SMK  
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 0  
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............49 52 56 60 65 67 69 71 72 72 72 72  
RH..............36 35 34 32 29 27 26 24 24 22 21 21  
20 FT WIND DIR..W W W W W W W W W W W W  
20 FT WIND SPD..6 6 7 9 13 14 15 16 16 16 16 16  
20 FT WIND GUST.7 10 10 13 18 19 20 22 22 22 22 22  
RIDGE WIND DIR..W W W W W W W W W W W W  
RIDGE WIND SPD..10 15 15 15 20 20 25 25 25 25 25 25  
MIX HGT (KFT)...0.5 0.5 0.5 2.5 5.0 7.0 8.5 9.0 10 11 10 9.5  
TRANSP WIND DIR.W W W W W W W W W W W W  
TRANSP WIND SPD.12 13 14 16 22 24 26 28 28 26 26 25  
SDSPL KT-FT/10006 6 8 34 93 147 191 220 238 238 230 210  
   
TONIGHT  
 
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF PCPN......0 PERCENT.  
CHANCE OF THUNDER...2 PERCENT.  
MIN TEMPERATURE.....AROUND 52.  
MAX HUMIDITY........38 PERCENT.  
WIND (20 FT)........WEST WINDS 7 TO 14 MPH WITH GUSTS TO AROUND 19  
MPH UNTIL 0200, THEN LIGHT.  
RIDGETOP WIND.......WEST 15 TO 20 MPH UNTIL 0300, THEN 10 TO 15  
MPH.  
MIXING HEIGHT.......8000 FT AGL UNTIL 2000, THEN 500 FT AGL.  
TRANSPORT WINDS.....WEST 15 TO 24 MPH UNTIL 0100, THEN 12 TO 14  
MPH.  
SMOKE DISPERSAL.....EXCELLENT UNTIL 2000. POOR AFTER 0300.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........5 10 10 10 15 15 20 25 20 20 30 35  
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 0  
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............70 68 65 62 59 58 55 55 54 53 53 53  
RH..............23 27 28 32 35 35 36 37 37 38 38 38  
20 FT WIND DIR..W W W W W W W W W W W SW  
20 FT WIND SPD..13 14 11 9 8 8 8 7 6 6 6 6  
20 FT WIND GUST.18 19 16 13 12 12 12 10 10 7 8 8  
RIDGE WIND DIR..W W W W W W W W W W W SW  
RIDGE WIND SPD..20 20 20 15 15 15 15 15 15 10 10 15  
MIX HGT (KFT)...9.5 8.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5  
TRANSP WIND DIR.W W W W W W W W W W W W  
TRANSP WIND SPD.24 23 18 16 15 15 15 14 13 12 12 13  
SDSPL KT-FT/1000199 157 16 8 7 7 8 7 6 6 6 6  
   
FRIDAY  
 
SKY/WEATHER.........PARTLY SUNNY (50-60 PERCENT). CHANCE OF SHOWERS  
AND THUNDERSTORMS IN THE AFTERNOON.  
CWR.................8 PERCENT.  
CHANCE OF PCPN......30 PERCENT.  
CHANCE OF THUNDER...27 PERCENT.  
MAX TEMPERATURE.....AROUND 72.  
MIN HUMIDITY........29 PERCENT.  
WIND (20 FT)........LIGHT WINDS UNTIL 1100, THEN WEST 7 TO 9 MPH.  
GUSTS UP TO 21 MPH. GUSTY AND ERRATIC WINDS  
EXPECTED NEAR THUNDERSTORMS IN THE AFTERNOON.  
RIDGETOP WIND.......WEST 10 TO 15 MPH.  
MIXING HEIGHT.......1000 FT AGL UNTIL 0900, THEN GRADUALLY INCREASING  
TO 8000 FT AGL THROUGH 1400, THEN DECREASING TO  
4000 FT AGL BY 1700.  
TRANSPORT WINDS.....WEST 10 TO 17 MPH.  
SMOKE DISPERSAL.....POOR UNTIL 1000, THEN GOOD EARLY IN THE MORNING  
INCREASING TO VERY GOOD IN THE AFTERNOON UNTIL  
1600, THEN FAIR EARLY IN THE MORNING INCREASING  
TO GOOD IN THE AFTERNOON.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........45 50 50 50 40 50 60 60 65 65 65 60  
WEATHER COV..... CHC CHC CHC CHC CHC CHC  
WEATHER TYPE.... RW RW RW RW RW RW  
TSTM COV........ CHC CHC CHC CHC CHC CHC  
CWR.............0 0 0 0 0 0 10 10 10 10 10 10  
CHC OF PCPN (%).10 10 10 10 10 10 30 30 30 30 30 30  
CHC OF THDR (%).0 0 0 0 0 0 30 30 30 30 30 30  
TEMP............52 53 58 63 67 69 70 70 68 67 66 65  
RH..............37 38 37 33 31 30 31 33 37 40 42 44  
20 FT WIND DIR..W W W SW W W W W W W W W  
20 FT WIND SPD..5 5 5 5 6 7 9 9 9 9 9 8  
20 FT WIND GUST.10 10 10 11 13 14 16 17 17 17 17 17  
RIDGE WIND DIR..W W W SW W W W W W W W W  
RIDGE WIND SPD..10 10 10 10 10 15 15 15 15 15 15 15  
MIX HGT (KFT)...0.5 0.5 1.0 3.0 6.0 7.0 8.0 7.5 6.0 4.5 4.5 4.0  
TRANSP WIND DIR.W W W W W W W W W W W SW  
TRANSP WIND SPD.10 10 10 12 15 16 17 17 17 17 16 15  
SDSPL KT-FT/10005 6 8 29 76 101 120 116 93 71 62 54  
   
FORECAST DAYS 3 THROUGH 5  
   
SATURDAY  
 
MOSTLY CLOUDY. CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS AROUND  
50 AND HIGHS IN THE LOWER 70S. SOUTHWEST WINDS 7 TO 11 MPH AND  
GUSTS AROUND 20 MPH.    
SUNDAY  
 
MOSTLY CLEAR. LOWS IN THE UPPER 40S AND HIGHS IN THE LOWER 70S.  
SOUTHWEST WINDS 9 TO 14 MPH AND GUSTS AROUND 25 MPH.    
MONDAY  
 
MOSTLY CLEAR. LOWS AROUND 50 AND HIGHS IN THE LOWER 70S. SOUTHWEST  
WINDS 9 TO 14 MPH AND GUSTS AROUND 25 MPH.  
 
 
FORECASTER...GERHARDT  
REQUESTED BY...TITUS PERKINS  
TYPE OF REQUEST...WILDFIRE  
.TAG 2518019.2/RIW  
.DELDT 07/17/25  
.FORMATTERVERSION 2.0.0  
.EMAIL TITUS.PERKINS@USDA.GOV  
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