887  
FNUS75 KRIW 301437  
FWSRIW  
 
SPOT FORECAST FOR MUDDY...CASPER DISPATCH  
NATIONAL WEATHER SERVICE RIVERTON WY  
837 AM MDT WED JUL 30 2025  
 
FORECAST IS BASED ON FORECAST START TIME OF 0800 MDT ON JULY 30.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE  
   
DISCUSSION  
 
EXPECT A LIGHT EASTERLY WIND THROUGH THIS MORNING INCREASING AFTER  
1200 WITH GUSTS TO 20 MPH THROUGH THE AFTERNOON. SHOWERS AND  
THUNDERSTORMS WILL START TO BUILD IN THE AREA AFTER 1200, THOUGH  
THE BEST CHANCES AT THE FIRE WILL BE BETWEEN 1800 AND 2300. THIS  
ACTIVITY WILL MOVE FROM THE SOUTHWEST TO NORTHEAST, AND COULD  
BRING A SUDDEN SHIFT FROM OUT OF THE EAST TO OUT OF THE WEST OR  
SOUTHWEST. THERE IS SOME MOISTURE IN THE ATMOSPHERE TODAY AND THIS  
COULD BRING BRIEF HEAVY RAIN THIS EVENING IF A CELL GOES DIRECTLY  
OVER THE FIRE. UNSETTLED CONDITIONS CONTINUE ON THURSDAY WITH  
ADDITIONAL STORM CHANCES BY LATE AFTERNOON.  
   
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS  
 
   
REST OF TODAY  
 
SKY/WEATHER.........MOSTLY SUNNY (40-50 PERCENT). CHANCE OF  
SHOWERS AND THUNDERSTORMS AFTER 1200.  
CWR.................8 PERCENT.  
CHANCE OF PCPN......30 PERCENT.  
CHANCE OF THUNDER...27 PERCENT.  
MAX TEMPERATURE.....AROUND 71.  
MIN HUMIDITY........56 PERCENT.  
WIND (20 FT)........LIGHT WINDS UNTIL 1100, THEN EAST 7 TO 12 MPH  
WITH GUSTS TO AROUND 20 MPH. GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS.  
RIDGETOP WIND.......EAST 10 TO 15 MPH UNTIL 1600, THEN AROUND 20  
MPH.  
MIXING HEIGHT.......INCREASING TO 4500 FT AGL BY 1400.  
TRANSPORT WINDS.....EAST 12 TO 18 MPH.  
SMOKE DISPERSAL.....INCREASING TO GOOD BY 1400.  
 
TIME (MDT) 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........30 30 30 25 25 25 30 30 45 60  
WEATHER COV..... SCH SCH CHC CHC CHC  
WEATHER TYPE.... RW RW RW RW RW  
TSTM COV........ SCH SCH CHC CHC CHC  
CWR.............0 0 0 0 10 10 10 10 10 10  
CHC OF PCPN (%).0 0 0 10 10 10 20 30 30 30  
CHC OF THDR (%).0 0 0 10 10 10 20 30 30 30  
TEMP............57 59 61 64 66 68 69 71 69 68  
RH..............79 79 73 68 63 60 58 56 57 59  
20 FT WIND DIR..E E E E E E E E E E  
20 FT WIND SPD..4 5 6 7 8 9 10 11 12 12  
20 FT WIND GUST.6 7 10 11 13 14 16 17 18 18  
RIDGE WIND DIR..E E E E E E E E E E  
RIDGE WIND SPD..10 10 10 15 15 15 15 15 20 20  
MIX HGT (KFT)...0.5 1.0 2.0 3.0 3.5 4.0 4.5 4.5 4.0 4.0  
TRANSP WIND DIR.E E E E E E E E E E  
TRANSP WIND SPD.12 12 12 13 14 15 17 17 18 18  
SDSPL KT-FT/10006 12 19 32 41 53 71 69 68 62  
   
TONIGHT  
 
SKY/WEATHER.........MOSTLY CLOUDY (65-75 PERCENT) THEN BECOMING  
PARTLY CLOUDY (40-50 PERCENT). CHANCE OF  
SHOWERS AND THUNDERSTORMS IN THE EVENING.  
CWR.................31 PERCENT DECREASING TO 1 PERCENT OVERNIGHT.  
CHANCE OF PCPN......40 PERCENT.  
CHANCE OF THUNDER...35 PERCENT.  
MIN TEMPERATURE.....AROUND 55.  
MAX HUMIDITY........81 PERCENT.  
WIND (20 FT)........GENERALLY EAST OR SOUTHEAST AROUND 10 MPH  
WITH GUSTS TO 15 MPH. GUSTY AND  
ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS.  
RIDGETOP WIND.......SOUTHEAST 15 TO 20 MPH UNTIL 2100, THEN SOUTH  
AROUND 10 MPH UNTIL 2200, THEN EAST UNTIL 0200,  
THEN SOUTH.  
MIXING HEIGHT.......DECREASING BELOW 500 FT AGL BY MIDNIGHT.  
TRANSPORT WINDS.....SOUTHEAST 18 TO 22 MPH UNTIL 2100, THEN WEST  
AROUND 14 MPH UNTIL 2200, THEN NORTHEAST AROUND  
16 MPH UNTIL 2300, THEN SOUTHEAST 16 TO 17 MPH.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........75 65 75 80 70 65 55 50 40 35 35 35  
WEATHER COV.....CHC CHC CHC CHC CHC SCH  
WEATHER TYPE....RW RW RW RW RW RW  
TSTM COV........CHC CHC CHC SCH SCH SCH  
CWR.............30 30 30 30 30 30 0 0 0 0 0 0  
CHC OF PCPN (%).30 30 40 40 30 20 10 10 10 0 0 0  
CHC OF THDR (%).30 30 40 20 20 20 10 10 10 0 0 0  
TEMP............67 62 61 59 58 57 56 56 56 56 56 55  
RH..............61 68 73 79 79 80 81 80 80 80 80 79  
20 FT WIND DIR..E SE SE S E E SE SE S S S S  
20 FT WIND SPD..11 10 9 6 9 9 9 9 9 9 10 9  
20 FT WIND GUST.17 14 14 8 14 14 14 14 14 14 14 14  
RIDGE WIND DIR..SE SE SE S E E SE SE S S S S  
RIDGE WIND SPD..20 15 15 10 15 15 15 15 15 15 15 15  
MIX HGT (KFT)...2.5 1.5 1.0 1.0 0.5 0.5 0.1 0.1 0.1 0.1 0.1 0.1  
TRANSP WIND DIR.SE SE SE W NE SE E SE S S S S  
TRANSP WIND SPD.22 21 18 14 16 16 16 16 16 16 17 16  
SDSPL KT-FT/100045 27 18 9 7 6 3 2 2 2 3 2  
   
THURSDAY  
 
SKY/WEATHER.........SUNNY (20-30 PERCENT). CHANCE OF SHOWERS  
AND THUNDERSTORMS AFTER 1200.  
CWR.................0 PERCENT INCREASING TO 14 PERCENT IN THE  
AFTERNOON.  
CHANCE OF PCPN......50 PERCENT.  
CHANCE OF THUNDER...39 PERCENT.  
MAX TEMPERATURE.....AROUND 76.  
MIN HUMIDITY........39 PERCENT.  
WIND (20 FT)........SOUTH AROUND 8 MPH BECOMING EAST 4 TO 8 MPH  
AFTER 1100 GUSTING 15 TO 20 MPH. GUSTY AND  
ERRATIC WINDS EXPECTED NEAR ANY THUNDERSTORMS.  
RIDGETOP WIND.......SOUTHEAST 10 TO 15 MPH UNTIL 1400, THEN EAST.  
MIXING HEIGHT.......100 FT AGL INCREASING TO 7000 FT AGL BY 1500.  
TRANSPORT WINDS.....SOUTH 12 TO 15 MPH UNTIL 1500, THEN WEST 15 TO  
16 MPH UNTIL 1700, THEN SOUTH AROUND 18 MPH.  
SMOKE DISPERSAL.....POOR INCREASING TO GOOD BY 1400.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........30 15 10 10 5 10 10 20 30 40 40 45  
WEATHER COV..... CHC CHC CHC CHC CHC CHC  
WEATHER TYPE.... RW RW RW RW RW RW  
TSTM COV........ SCH SCH SCH CHC CHC CHC  
CWR.............0 0 0 0 0 0 10 10 10 10 10 10  
CHC OF PCPN (%).0 0 0 0 0 0 50 50 50 50 50 50  
CHC OF THDR (%).0 0 0 0 0 0 20 20 20 40 40 40  
TEMP............55 57 60 63 65 68 70 72 74 74 73 71  
RH..............79 78 72 65 62 57 51 46 42 40 41 44  
20 FT WIND DIR..S S SE SE SE E E E E E E SE  
20 FT WIND SPD..8 8 8 7 6 6 6 6 6 7 7 8  
20 FT WIND GUST.13 14 14 14 14 13 13 14 16 17 17 17  
RIDGE WIND DIR..S S SE SE SE E E E E E E SE  
RIDGE WIND SPD..15 15 15 15 15 10 10 10 15 15 15 15  
MIX HGT (KFT)...0.1 0.1 0.5 1.0 2.0 3.0 3.5 5.0 6.0 7.0 6.0 4.5  
TRANSP WIND DIR.S S S SE SE SE S S SW W SW S  
TRANSP WIND SPD.15 15 15 14 13 12 12 12 13 15 16 18  
SDSPL KT-FT/10001 2 6 14 21 28 36 48 66 93 82 72  
   
FORECAST DAYS 3 THROUGH 5  
   
FRIDAY  
 
PARTLY CLOUDY. CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS IN THE  
MID 50S. HIGHS IN THE UPPER 70S. SOUTHWEST WINDS 5 TO 10 MPH.    
SATURDAY  
 
MOSTLY CLEAR. LOWS IN THE MID 50S. HIGHS IN THE UPPER 70S. WEST  
WINDS 4 TO 8 MPH.   
SUNDAY  
 
PARTLY CLOUDY. SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. LOWS  
IN THE LOWER 50S. HIGHS IN THE MID 70S. NORTHWEST WINDS 4 TO 8 MPH.  
 
 
FORECASTER...MYERS  
REQUESTED BY...JON BISIAR  
TYPE OF REQUEST...WILDFIRE  
.TAG 2518870.0/RIW  
.DELDT 07/30/25  
.FORMATTERVERSION 2.0.0  
.EMAIL WYCPC@FIRENET.GOV  
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