Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
618
FNUS75 KRIW 181137
FWSRIW
Spot Forecast for Horse...USFS
National Weather Service Riverton WY
537 AM MDT Fri Jul 18 2025
Forecast is based on forecast start time of 0600 MDT on July 18.
If conditions become unrepresentative, contact the National Weather
Service
.DISCUSSION...
Cooler today with higher relative humidity and increasing cloud
cover. Light west winds increase after 1000L to 10-15 mph and
continue through 1900L at the latest. Expect occasional gusts,
outside of thunderstorms, around 20 mph between 1100L-1600L.
Shower and thunderstorm chances increase between 1300L-1400L and
continue through much of the day and diminish by 2100L.
Thunderstorms could produce 40 mph gusty and erratic outflows.
Mixing and smoke dispersal will be very good to excellent from
1100L to 1300L, before precipitation begins. Good relative
humidity recovery tonight. Similar conditions on Saturday with
more isolated afternoon precipitation chances.
...Thunderstorms imply strong gusty and erratic winds...
.TODAY...
Sky/weather.........Mostly sunny (40-50 percent) then becoming
mostly cloudy (70-80 percent). Slight chance of
showers and thunderstorms early in the
afternoon. Slight chance of dry thunderstorms
late in the afternoon.
CWR.................0 percent increasing to 27 percent in the
afternoon.
Chance of pcpn......50 percent.
Chance of thunder...30 percent.
Max temperature.....Around 70.
Min humidity........33 percent.
Wind (20 ft)........Light winds until 0900, then west 7 to 12 mph
with gusts to around 17 mph until 1700, then
light. Gusty and erratic winds expected near
thunderstorms late in the afternoon.
Ridgetop wind.......West 10 to 15 mph until 1100. Around 10 mph
after 1700.
Mixing height.......500 ft AGL until 0900, then gradually increasing
to 10000 ft AGL after 1200, then decreasing to
7000 ft AGL after 1500.
Transport winds.....West 10 to 18 mph until 1300, then 13 to 20
mph.
Smoke dispersal.....Poor until 1000, then increasing to very good
to excellent in the afternoon until 1500.
TIME (MDT) MID 1AM 2AM 3AM 4AM 5AM 6AM 7AM 8AM 9AM 10A 11A
Sky (%).........30 35 35 35 30 35 25 35 60 70 75 75
Weather cov..... SCH
Weather type.... RW
Tstm cov........ SCH SCH SCH SCH
CWR.............0 0 0 0 0 0 30 30 30 30 30 30
Chc of pcpn (%).0 0 0 0 0 10 0 10 20 40 50 40
Chc of thdr (%).0 0 0 0 0 0 0 10 20 30 30 30
Temp............59 58 62 67 67 68 69 69 69 66 65 64
RH..............38 37 36 35 34 33 33 35 38 44 49 54
20 FT wind dir..W W W W W W W W W W NW W
20 FT wind spd..6 5 6 7 8 11 11 12 9 11 7 6
20 FT wind gust.10 6 10 10 12 16 16 17 13 16 10 7
Ridge wind dir..W W W W W W W W W W NW W
Ridge wind spd..15 10 15 15 15 20 20 20 15 20 15 10
Mix hgt (kft)...0.5 0.5 0.5 2.5 6.0 7.0 8.5 10 9.0 7.0 6.5 6.0
Transp wind dir.W W W W W W W W W W W W
Transp wind spd.13 10 13 14 17 18 18 20 17 18 15 13
SDspl kt-ft/10006 5 7 30 90 110 136 167 138 112 87 67
.TONIGHT...
Sky/weather.........Mostly cloudy (65-75 percent) then becoming
partly cloudy (35-45 percent). Chance of rain
showers and thunderstorms through the evening.
Slight chance of rain showers late in the
evening.
CWR.................13 percent decreasing to 0 percent overnight.
Chance of pcpn......40 percent.
Chance of thunder...22 percent.
Min temperature.....Around 47.
Max humidity........77 percent.
Wind (20 ft)........South winds around 8 mph until 2000, then
light. Gusty and erratic winds expected near
thunderstorms in the evening.
Ridgetop wind.......Southeast 10 to 15 mph until 0100, then light
until 0300, then southwest around 10 mph.
Mixing height.......2500 ft AGL until 2000, then 500 ft AGL.
Transport winds.....Southwest 7 to 15 mph.
Smoke dispersal.....Fair until 1900. Poor after 2000.
TIME (MDT) 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10P 11P
Sky (%).........70 80 80 75 65 60 55 50 50 50 35 25
Weather cov.....CHC CHC CHC SCH SCH
Weather type....RW RW RW RW RW
Tstm cov........SCH SCH SCH SCH SCH
CWR.............10 10 10 10 10 10 0 0 0 0 0 0
Chc of pcpn (%).40 40 30 20 10 10 10 0 0 0 0 0
Chc of thdr (%).20 20 20 10 10 10 10 0 0 0 0 0
Temp............61 58 57 56 52 50 49 49 49 49 48 48
RH..............61 67 72 77 74 74 71 71 69 68 68 69
20 FT wind dir..S S SE SE S S SE W SW W SW W
20 FT wind spd..8 8 5 6 4 3 4 2 2 3 4 5
20 FT wind gust.12 12 6 7 6 4 6 4 6 6
Ridge wind dir..S S SE SE S S SE W SW W SW W
Ridge wind spd..15 15 10 10 10 10 10 5 5 10 10 10
Mix hgt (kft)...3.5 2.5 1.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
Transp wind dir.S S SW S S S S SW SW W W W
Transp wind spd.15 15 10 12 9 8 9 7 7 8 9 10
SDspl kt-ft/100048 33 12 5 4 4 4 3 3 4 5 5
.SATURDAY...
Sky/weather.........Sunny (20-30 percent). Chance of showers and
thunderstorms in the afternoon.
CWR.................0 percent.
Chance of pcpn......30 percent.
Chance of thunder...26 percent.
Max temperature.....Around 71.
Min humidity........34 percent.
Wind (20 ft)........Light winds until 1000, then west 7 to 12 mph
with gusts to around 20 mph. Gusty and erratic
winds expected near thunderstorms in the
afternoon.
Ridgetop wind.......West 10 to 15 mph until 1300, then around 20
mph.
Mixing height.......1500 ft AGL until 0900. 8500 ft AGL after 1200.
Transport winds.....West 10 to 18 mph until 1100, then 21 to 23
mph.
Smoke dispersal.....Poor until 0900. Very good early in the morning
increasing to excellent in the afternoon after
1200.
TIME (MDT) MID 1AM 2AM 3AM 4AM 5AM 6AM 7AM 8AM 9AM 10A 11A
Sky (%).........15 15 5 5 5 10 15 25 30 40 35 30
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 0 0 0 0 0 0
Chc of pcpn (%).10 10 10 10 10 10 30 30 30 30 30 30
Chc of thdr (%).0 0 0 10 10 10 30 30 30 30 30 30
Temp............48 49 54 60 63 66 68 69 70 70 70 69
RH..............66 69 64 55 48 42 37 35 34 34 33 33
20 FT wind dir..W W W SW W W W W W W W W
20 FT wind spd..5 5 6 6 7 9 10 11 12 12 12 12
20 FT wind gust.8 10 10 12 14 16 18 18 19 20 20 20
Ridge wind dir..W W W SW W W W W W W W W
Ridge wind spd..10 10 10 15 15 15 15 20 20 20 20 20
Mix hgt (kft)...0.5 0.5 1.5 2.5 5.5 7.0 8.5 8.0 8.0 7.5 7.5 7.5
Transp wind dir.W W W W W W W W W W W W
Transp wind spd.10 10 12 14 18 21 22 22 23 23 23 23
SDspl kt-ft/10005 6 13 33 87 126 162 155 156 148 147 146
.FORECAST DAYS 3 THROUGH 5...
.SUNDAY...
Mostly clear. Lows in the upper 40s and highs in the lower 70s.
West-southwest winds 9 to 15 mph and gusts between 25 to 30 mph.
.MONDAY...
Mostly clear. Lows around 50 and highs in the lower 70s. Southwest
winds 9 to 14 mph and gusts between 25 to 30 mph.
.TUESDAY...
Mostly clear. Lows around 50 and highs in the lower 70s. Southwest
winds 8 to 13 mph and gusts between 20 to 25 mph.
$$
Forecaster...Gerhardt
Requested by...Titus Perkins
Type of request...WILDFIRE
.TAG 2518019.3/RIW
.DELDT 07/18/25
.FormatterVersion 2.0.0
.EMAIL titus.perkins@usda.gov