Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
289
FNUS75 KRIW 312115
FWSRIW
Spot Forecast for Willow Creek Fire...BLM
National Weather Service Riverton WY
315 PM MDT Sun Aug 31 2025
Forecast is based on forecast start time of 0600 MDT on September 01.
If conditions become unrepresentative, contact the National Weather
Service
.DISCUSSION...
Winds will be out of the southeast to start the day, generally
around 8 mph with occasional gusts up to 15 mph. Winds shift to be
from the south by 1000L, and then from the southwest by about 1500L.
Winds increase slightly to be about 10 mph around 1100L, with gusts
around 15 mph through the afternoon. No rain is expected, with a
mostly clear sky; the only clouds would be some afternoon cumulus.
Winds shift Monday night, being southeasterly around midnight.
Looking ahead, the first half of the week remains dry, with similar
high temperatures and minimum RHs each day. Next chance (15%-20%)
for rain is not until Friday, though confidence is low at this range.
...Thunderstorms imply strong gusty and erratic winds...
.LABOR DAY...
Sky/weather.........Sunny (5-15 percent).
CWR.................0 percent.
Chance of pcpn......0 percent.
Chance of thunder...0 percent.
Max temperature.....Mid-70s.
Min humidity........19-23 percent.
Wind (20 ft)........Southeast winds 8 mph until 0900, then
south around 10 mph until 0100, the southwest.
Gusts up to 15 mph.
Ridgetop wind.......Southeast 10 to 15 mph until 1300, then
southwest.
Mixing height.......9500 ft AGL after 1500.
Transport winds.....Southeast 12 mph until 1100, then
southwest 12 to 15 mph.
Smoke dispersal.....Poor until 1000, 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 10 10 5 5 5 10 10 10 15 15 15
Weather cov.....PTY PTY PTY PTY PTY PTY PTY
Weather type....SMK SMK SMK SMK SMK 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............51 51 53 57 64 68 72 74 74 74 74 74
RH..............40 41 40 36 30 26 23 22 21 20 21 21
20 FT wind dir..SE SE SE SE S S S S SW SW SW SW
20 FT wind spd..8 8 8 9 8 9 9 9 9 9 9 7
20 FT wind gust.12 12 12 14 12 13 13 13 13 13 13 10
Ridge wind dir..SE SE SE SE S S S S SW SW SW SW
Ridge wind spd..10 10 10 10 15 15 15 15 15 15 15 10
Mix hgt (kft)...0.1 0.1 0.1 0.1 1.5 4.0 7.0 8.0 8.5 9.0 9.0 9.5
Transp wind dir.SE SE SE SE S S S S S SW SW SW
Transp wind spd.12 12 12 12 13 14 15 15 14 14 14 12
SDspl kt-ft/100018 17 17 16 45 84 124 135 143 148 140 121
.MONDAY NIGHT...
Sky/weather.........Mostly clear (15-20 percent).
CWR.................0 percent.
Chance of pcpn......0 percent.
Chance of thunder...0 percent.
Min temperature.....Low 50s.
Max humidity........37-41 percent.
Wind (20 ft)........West winds 5 to 8 mph turning north and then northeast
between 2000 and 2400. East to southeast winds
around 8 mph after 2400.
Ridgetop wind.......Southwest around 10 mph until 2100, then east.
Mixing height.......9000 ft AGL until 1900.
Transport winds.....West around 10 mph until 2100, then northwest
around 8 mph until 2300, then northeast around
9 mph until 0200, then east.
Smoke dispersal.....Good until 1900. Poor after 2000.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........30 25 20 15 15 10 10 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 0 0 0 0 0 0
Chc of thdr (%).0 0 0 0 0 0 0 0 0 0 0 0
Temp............73 69 65 62 60 59 58 57 56 55 54 53
RH..............22 26 30 33 35 36 36 37 37 38 38 38
20 FT wind dir..SW W S E E E E E E E E E
20 FT wind spd..6 5 4 4 5 5 6 6 6 6 6 6
20 FT wind gust.11 8 7 6 6 7 8 8 7 7 7 7
Ridge wind dir..SW W S E E E E E E E E E
Ridge wind spd..10 10 10 10 10 10 10 10 10 10 10 10
Mix hgt (kft)...9.0 1.0 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1
Transp wind dir.SW W W NW N NE E E E E SE SE
Transp wind spd.10 8 8 8 8 9 9 9 9 9 9 9
SDspl kt-ft/100098 23 9 10 12 12 13 13 12 12 12 12
.TUESDAY...
Sky/weather.........Sunny (5-15 percent).
CWR.................0 percent.
Chance of pcpn......0 percent.
Chance of thunder...0 percent.
Max temperature.....Mid-70s.
Min humidity........19-23 percent.
Wind (20 ft)........Southeast winds around 7 mph turning south
and then southwest between 0700 and 1100. Then,
west to northwest winds 8 to 10 mph with gusts
15 to 18 mph.
Ridgetop wind.......Southeast around 10 mph until 1100, then
northwest.
Mixing height.......3000 ft AGL at 1000, increasing to around
10500 ft AGL around 1300.
Transport winds.....Southeast around 8 mph until 1000. Northwest 10 to
14 mph after 1200.
Smoke dispersal.....Poor until 1000 increasing to very good in the ]
afternoon after 1400.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........10 10 5 5 5 10 10 10 15 15 15 15
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............53 55 57 60 64 68 71 73 74 74 74 74
RH..............38 38 37 35 31 27 23 21 20 20 20 20
20 FT wind dir..E E SE SE S W W NW NW NW NW NW
20 FT wind spd..6 6 5 5 5 5 5 6 6 7 7 7
20 FT wind gust.7 7 6 6 7 8 10 11 13 14 14 14
Ridge wind dir..E E SE SE S W W NW NW NW NW NW
Ridge wind spd..10 10 10 10 10 10 10 10 10 10 15 15
Mix hgt (kft)...0.1 0.1 0.1 0.1 3.0 6.0 8.5 9.5 10 11 9.5 8.5
Transp wind dir.SE SE S S S W W W NW NW NW NW
Transp wind spd.9 8 8 8 8 8 9 10 12 12 13 13
SDspl kt-ft/100012 13 11 12 32 61 97 113 119 139 140 130
.FORECAST DAYS 3 THROUGH 5...
.WEDNESDAY...
Mostly clear. Lows in the lower 50s. Highs in the mid 70s.
Afternoon northwest winds around 10 mph, with gusts 15 to 20 mph.
.THURSDAY...
Mostly clear. Lows in the lower 50s. Highs in the mid 70s.
Afternoon northwest 8 to 10 mph, with gusts around 15 mph.
.FRIDAY...
Mostly clear. Slight chance (15%-20%) of showers and thunderstorms.
Lows in the lower 50s. Highs in the mid 70s. Afternoon west to
northwest winds 7 to 10 mph, with gusts to 15 mph possible.
$$
Forecaster...Wittmann
Requested by...Dionysius Nicolas - Plans Section
Type of request...WILDFIRE
.TAG 2520679.5/RIW
.DELDT 08/31/25
.FormatterVersion 2.0.0
.EMAIL dnicolas@blm.gov,dionysius-caesar_nicolas@firenet.gov