Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
868
FNUS75 KRIW 161156
FWSRIW
Spot Forecast for Grouse Mountain RX...USFS
National Weather Service Riverton WY
556 AM MDT Thu Oct 16 2025
Forecast is based on ignition time of 0600 MDT on October 16.
If conditions become unrepresentative, contact the National Weather
Service
.DISCUSSION...
Wetter and cooler conditions will be seen today as a low pressure
system moves across Wyoming. This will bring snow showers through
the day, most persistent in the afternoon. A little lightning
cannot be ruled out as well. A breezy northwest wind will develop
after 1200. Precipitation will begin to wane after sunset, coming
to an end by midnight. Total snow accumulation of 2 to 4 inches
is expected with amounts increasing at higher elevations. Friday
will be slightly warmer and dry as clouds clear by late morning.
...Thunderstorms imply strong gusty and erratic winds...
.TODAY...
Sky/weather.........Cloudy (85-95 percent). Snow showers through
the day with a slight chance of a thunderstorm.
CWR.................55 percent increasing to 80 percent in the
afternoon.
Chance of pcpn......90 percent.
Chance of thunder...15 percent.
Max temperature.....Around 34.
Min humidity........90 percent.
Wind (20 ft)........Northwest 6 to 10 mph with gusts to 15 mph.
Ridgetop wind.......Northwest 10 to 15 mph.
Mixing height.......Increasing to 2000 ft AGL by 1300.
Transport winds.....Northwest 9 to 16 mph.
Smoke dispersal.....Poor.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........75 75 90 85 90 90 90 95 100 95 95 95
Weather cov.....SCT SCT NUM DEF DEF DEF NUM DEF DEF DEF NUM DEF
Weather type....SW SW SW SW SW SW SW SW SW SW SW SW
Tstm cov........ ISO ISO ISO ISO ISO ISO
CWR.............60 60 60 60 60 60 80 80 80 80 80 80
Chc of pcpn (%).50 50 70 80 80 80 70 90 90 80 70 80
Chc of thdr (%).10 10 10 10 10 10 10 10 10 20 20 20
Temp............31 30 31 31 32 33 33 34 33 34 33 32
RH..............97 97 99 99 97 96 95 94 94 93 94 93
20 FT wind dir..N NW N N NW NW NW NW NW NW NW NW
20 FT wind spd..4 4 5 5 6 6 8 8 9 9 9 9
20 FT wind gust.6 6 6 6 7 10 12 12 13 13 13 13
Ridge wind dir..N NW N N NW NW NW NW NW NW NW NW
Ridge wind spd..10 10 10 10 10 15 15 15 15 15 15 15
Mix hgt (kft)...0.5 0.5 0.5 0.5 1.0 1.5 1.5 2.0 2.0 2.0 2.0 1.5
Transp wind dir.N N N N N N N NW NW NW NW NW
Transp wind spd.9 9 10 10 12 13 15 15 16 16 16 16
SDspl kt-ft/10004 3 4 6 9 14 22 23 30 29 27 23
.TONIGHT...
Sky/weather.........Cloudy (90-100 percent). Snow showers mostly
coming to an end around midnight.
CWR.................30 percent decreasing to 1 percent overnight.
Chance of pcpn......70 percent.
Chance of thunder...5 percent.
Min temperature.....Around 24.
Max humidity........97 percent.
Wind (20 ft)........Northwest winds 7 to 8 mph until 2400, then
light.
Ridgetop wind.......Northwest 10 to 15 mph.
Mixing height.......Decreasing to 500 ft AGL by 0300.
Transport winds.....Northwest 10 to 15 mph.
Smoke dispersal.....Poor.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........95 100 95 95 95 85 85 90 90 90 85 85
Weather cov.....NUM NUM SCT ISO ISO ISO SCT ISO
Weather type....SW SW SW SW SW SW SW SW
Tstm cov........
CWR.............30 30 30 30 30 30 0 0 0 0 0 0
Chc of pcpn (%).70 60 50 20 20 20 15 10 10 10 10 10
Chc of thdr (%).10 10 10 0 0 0 0 0 0 0 0 0
Temp............32 30 30 29 29 29 29 28 28 28 27 27
RH..............97 98 98 97 97 96 96 97 97 96 95 92
20 FT wind dir..NW NW NW NW NW NW NW NW NW NW NW NW
20 FT wind spd..8 8 8 7 7 7 6 6 6 6 6 5
20 FT wind gust.12 12 12 10 10 10 10 7 7 7 7 8
Ridge wind dir..NW NW NW NW NW NW NW NW NW NW NW NW
Ridge wind spd..15 15 15 15 15 15 15 10 10 10 10 10
Mix hgt (kft)...1.5 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.5 0.5 0.5 0.5
Transp wind dir.NW NW NW NW NW NW NW W W W W W
Transp wind spd.15 15 15 14 14 14 13 12 13 12 12 10
SDspl kt-ft/100017 15 15 14 14 14 14 13 15 7 7 10
.FRIDAY...
Sky/weather.........Mostly cloudy (75-85 percent) then becoming
mostly sunny (35-45 percent).
CWR.................0 percent.
Chance of pcpn......10 percent.
Chance of thunder...1 percent.
Max temperature.....Around 37.
Min humidity........74 percent.
Wind (20 ft)........West around 5 mph.
Ridgetop wind.......West 10 to 15 mph.
Mixing height.......Increasing to 3000 ft AGL by 1500.
Transport winds.....West 10 to 17 mph.
Smoke dispersal.....Poor to fair.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........90 80 70 70 45 45 45 40 35 35 30 30
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 (%).0 0 0 0 0 0 0 0 0 0 0 0
Temp............26 25 25 26 29 31 33 35 36 37 36 35
RH..............88 94 94 94 83 79 78 75 73 72 72 72
20 FT wind dir..W NW W W W W W W W W W W
20 FT wind spd..5 4 4 4 4 5 5 6 6 6 6 6
20 FT wind gust.10 10 10 10 10 11 12 13 14 14 14 14
Ridge wind dir..W NW W W W W W W W W W W
Ridge wind spd..10 10 10 10 10 10 10 10 10 15 15 15
Mix hgt (kft)...1.0 0.5 0.5 0.5 1.0 1.5 2.0 2.5 2.5 3.0 2.5 2.0
Transp wind dir.W W W W W W W W W W W W
Transp wind spd.10 9 9 9 9 10 12 14 15 17 16 15
SDspl kt-ft/100010 2 2 4 9 14 19 27 34 44 33 24
.FORECAST DAYS 3 THROUGH 5...
.SATURDAY...
Partly cloudy. Chance of snow showers in the morning. Lows in the
mid 20s. Highs in the mid 30s. West winds 4 to 8 mph.
.SUNDAY...
Mostly clear. Slight chance of showers and snow showers in the
afternoon. Lows in the lower 20s. Highs in the mid 40s. Southwest
winds 6 to 10 mph with gusts to 15 mph.
.MONDAY...
Colder. Snow showers likely. Lows in the mid 20s. Highs in the
upper 20s. West winds 6 to 10 mph.
$$
Forecaster...Myers
Requested by...Paul Hood
Type of request...PRESCRIBED
.TAG 2523564.2/RIW
.DELDT 10/16/25
.FormatterVersion 2.0.0
.EMAIL paul_hood@nps.gov,patrick.tenney@usda.gov,Eli.Berman@usda.gov,eric.hawes@usda.gov