Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
629
FNUS75 KRIW 171937
FWSRIW
Spot Forecast for Bare...USFS
National Weather Service Riverton WY
137 PM MDT Mon Aug 17 2026
Forecast is based on forecast start time of 0600 MDT on August 18.
If conditions become unrepresentative, contact the National Weather
Service
.DISCUSSION...
Tuesday morning winds will be light (under 10 mph) from the
southwest. Winds shift to be from the west around 1000L, increasing
to sustained speeds around 10 mph and afternoon gusts generally 20
to 25 mph. Winds decrease between 1900 and 2100.
Moisture begins to increase Monday night, with light rain shower
chances (15-20%) through Tuesday morning. Chances increase late
Tuesday morning (to 20-40%), which also includes the chance for
thunderstorms, continuing through the rest of the day. Gusty outflow
winds to around 40 mph and lightning are the main hazards with
storms. Low chances continue late Tuesday, become less than 10
percent around midnight.
...Thunderstorms imply strong gusty and erratic winds...
.TUESDAY...
Sky/weather.........Partly sunny (60-70 percent). Scattered rain
showers through the day. Isolated thunderstorms
in the afternoon.
CWR.................5 percent.
Chance of pcpn......40 percent.
Chance of thunder...25 percent.
Max temperature.....Around 70.
Min humidity........33-37 percent.
Wind (20 ft)........Light southwest winds around 6 mph until 1000,
then west around 10 mph with gusts up to around
25 mph. Gusty and erratic winds expected near
thunderstorms in the afternoon.
Ridgetop wind.......Southwest 10 to 15 mph until 1200, then west 15
to 20 mph.
Mixing height.......1000 ft AGL until 1000. 7500 ft AGL after 1200.
Transport winds.....West 10 to 15 mph until 1500, then around 20
mph.
Smoke dispersal.....Poor until 1000. Very good after 1300.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........65 60 55 50 70 80 70 65 75 70 80 70
Weather cov.....ISO ISO ISO ISO ISO SCT SCT SCT SCT SCT SCT ISO
Weather type....RW RW RW RW RW RW RW RW RW RW RW RW
Tstm cov........ ISO ISO ISO
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
Chc of pcpn (%).20 20 20 20 20 30 30 30 30 30 40 20
Chc of thdr (%).10 10 10 10 10 10 10 10 10 20 20 10
Temp............54 52 54 57 61 63 65 66 68 68 68 68
RH..............61 66 67 63 57 50 44 42 39 39 38 37
20 FT wind dir..SW SW W SW W W W W W W W W
20 FT wind spd..6 6 4 5 6 7 9 11 10 11 10 10
20 FT wind gust.8 10 10 11 12 13 16 17 18 19 19 19
Ridge wind dir..SW SW W SW W W W W W W W W
Ridge wind spd..10 15 10 10 10 15 15 20 15 20 15 15
Mix hgt (kft)...0.5 0.5 0.5 1.0 3.5 5.0 6.5 7.5 6.5 7.0 7.0 7.0
Transp wind dir.SW W W W W W W W W W W W
Transp wind spd.12 13 10 10 13 14 16 18 18 20 20 20
SDspl kt-ft/10006 6 5 10 37 61 88 124 106 117 121 118
.TUESDAY NIGHT...
Sky/weather.........Mostly cloudy (50-60 percent) until 1900, then
becoming partly cloudy (35-45 percent).
CWR.................0 percent.
Chance of pcpn......15 percent.
Chance of thunder...5 percent.
Min temperature.....Around 50.
Max humidity........55-60 percent.
Wind (20 ft)........West winds around 10 mph with gusts to around 20
mph until 2000, then light west-southwest
5 to 8 mph.
Ridgetop wind.......West 10 to 15 mph.
Mixing height.......5000 ft AGL until 2000, then 500 ft AGL.
Transport winds.....West 10 to 15 mph.
Smoke dispersal.....Good until 2000, then poor.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........55 50 40 35 35 35 40 35 30 25 25 25
Weather cov.....
Weather type....
Tstm cov........
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
Chc of pcpn (%).10 10 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............69 67 64 60 57 56 55 55 54 52 51 51
RH..............37 41 45 50 53 55 55 55 56 57 57 58
20 FT wind dir..W W W SW W W W W W W W W
20 FT wind spd..9 7 6 5 5 5 5 4 4 4 4 4
20 FT wind gust.18 16 13 10 10 8 8 7 7 7 7 7
Ridge wind dir..W W W SW W W W W W W W W
Ridge wind spd..15 15 10 10 10 10 10 10 10 10 10 10
Mix hgt (kft)...6.0 5.0 0.5 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.17 14 12 12 12 10 10 10 10 10 10 10
SDspl kt-ft/100089 62 6 6 6 5 5 5 5 5 5 5
.WEDNESDAY...
Sky/weather.........Sunny (15-25 percent).
CWR.................0 percent.
Chance of pcpn......5 percent.
Chance of thunder...0 percent.
Max temperature.....Around 72.
Min humidity........22-26 percent.
Wind (20 ft)........Light west winds 5 to 8 mph until 1100, then
west 10 to 15 mph with gusts to around 25 mph.
Ridgetop wind.......West 10 to 15 mph until 1400, then around 20
mph.
Mixing height.......2000 ft AGL until 1000. 9000 ft AGL after 1200.
Transport winds.....West 10 to 15 mph until 1200, then 1around 20 mph.
Smoke dispersal.....Poor until 0900, increasing to excellent in the
afternoon after 1200.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........25 20 15 10 10 10 10 10 10 10 10 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............50 52 55 57 61 64 68 69 71 72 72 71
RH..............58 55 53 50 43 37 30 29 27 26 26 25
20 FT wind dir..W W W W W W W W W W W NW
20 FT wind spd..4 3 3 3 5 7 9 10 11 11 11 11
20 FT wind gust.7 6 6 6 10 14 18 18 20 21 20 20
Ridge wind dir..W W W W W W W W W W W NW
Ridge wind spd..10 10 10 10 10 15 15 15 20 20 20 20
Mix hgt (kft)...0.5 1.0 1.5 2.0 4.0 6.5 8.5 8.5 8.5 9.0 8.0 7.5
Transp wind dir.W W W W W W W W W W W W
Transp wind spd.10 10 10 10 14 17 21 21 21 21 20 18
SDspl kt-ft/10005 9 14 18 51 96 154 156 157 159 138 118
.FORECAST DAYS 3 THROUGH 5...
.THURSDAY...
Mostly clear. Lows around 50. Highs in the mid 70s. West winds
around 10 mph with afternoon gusts to around 20 mph. Minimum
humidity around 25 percent.
.FRIDAY...
Partly cloudy. Slight chance of showers and thunderstorms. Lows
in the mid 50s. Highs in the mid 70s. West to southwest winds
around 8 mph with afternoon gusts to around 15 mph. Minimum
humidity around 28 percent.
.SATURDAY...
Mostly cloudy. Showers likely and chance of thunderstorms. Lows
in the mid 50s. Highs in the lower 70s. Southwest winds around
10 mph with afternoon gusts to around 20 mph. Minimum humidity
around 40 percent.
$$
Forecaster...Wittmann
Requested by...Stan Mitchem
Type of request...WILDFIRE
.TAG 2619432.6/RIW
.DELDT 08/17/26
.FormatterVersion 2.0.0
.EMAIL Stan@mitchem.com,paul_mitchem@firenet.gov