Spot Forecast
Issued by NWS Riverton, WY
Issued by NWS Riverton, WY
659
FNUS75 KRIW 300120
FWSRIW
Spot Forecast for Bull Fire...USFS
National Weather Service Riverton WY
720 PM MDT Mon Sep 29 2025
Forecast is based on forecast start time of 2000 MDT on September 29.
If conditions become unrepresentative, contact the National Weather
Service
.DISCUSSION...
An isolated rain shower remains possible (10%) overnight, with
increasing cloud cover and rain chances by sunrise. Rain chances
continue to increase through Tuesday morning, with the best chance
(50-60%) Tuesday afternoon. There will be scattered thunderstorms
in the afternoon as well. Total rainfall amounts will be about
0.15"-0.3" at the fire through Tuesday night, but most of that
will fall Tuesday afternoon. Temperatures will remain much too
warm for any concerns of snowfall at the fire.
Wind will remain light overnight becoming 10-15 mph from the
southwest late Tuesday morning. Wind will become light again by
sunset Tuesday evening. Precipitation chances end by Wednesday
morning with a warming and drying trend for Wednesday and
Thursday. Next large weather system will arrive this weekend.
...Thunderstorms imply strong gusty and erratic winds...
.REST OF TONIGHT...
Sky/weather.........Partly cloudy (35-45 percent) then becoming
mostly cloudy (55-65 percent). Slight chance of
rain showers early in the morning.
CWR.................0 percent.
Chance of pcpn......20 percent.
Chance of thunder...4 percent.
Min temperature.....Around 41.
Max humidity........93 percent.
Wind (20 ft)........Light winds.
Ridgetop wind.......South 10 to 15 mph.
Mixing height.......500 ft AGL.
Transport winds.....South 10 to 15 mph.
Smoke dispersal.....Poor.
TIME (MDT) 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........35 30 35 40 40 40 40 40 50 60
Weather cov..... SCH
Weather type.... RW
Tstm cov........
CWR.............0 0 0 0 0 0 0 0 0 0
Chc of pcpn (%).0 0 0 0 0 10 10 10 10 20
Chc of thdr (%).0 0 0 0 0 0 0 0 0 0
Temp............49 47 45 45 44 44 44 44 43 44
RH..............71 83 79 79 86 89 89 93 93 89
20 FT wind dir..SE SE SE SE S S S S S S
20 FT wind spd..4 5 6 5 6 7 8 6 6 6
20 FT wind gust.6 7 8 7 10 11 12 10 10 10
Ridge wind dir..SE SE SE SE S S S S S S
Ridge wind spd..10 10 10 10 15 15 15 15 15 15
Mix hgt (kft)...0.1 0.5 0.1 0.5 0.1 0.5 0.5 0.1 0.5 0.1
Transp wind dir.S SE SE SE S S S S S S
Transp wind spd.9 10 12 10 13 14 15 13 14 13
SDspl kt-ft/10002 2 2 2 3 3 3 3 3 3
.TUESDAY...
Sky/weather.........Mostly cloudy (70-80 percent). Chance of rain
showers in the morning, then rain showers
likely and chance of thunderstorms in the
afternoon.
CWR.................4 percent increasing to 58 percent in the
afternoon.
Chance of pcpn......60 percent.
Chance of thunder...32 percent.
Max temperature.....Around 50.
Min humidity........70 percent.
Wind (20 ft)........Light winds until 1000, then southwest 7 to 12
mph until 1300, then 10 to 15 mph. Gusts up to
18 mph increasing to 21 mph in the afternoon.
Gusty and erratic winds expected near thunderstorms
in the afternoon.
Ridgetop wind.......Southwest 10 to 15 mph until 1300, then 15 to
20 mph.
Mixing height.......1000 ft AGL until 1000, then 4000 ft AGL until
1500, then 2000 ft AGL.
Transport winds.....Southwest 12 to 20 mph.
Smoke dispersal.....Poor until 1100, then increasing to good until
1400, then fair until 1500, then poor.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........65 65 60 60 60 60 65 70 75 85 80 75
Weather cov.....CHC SCH SCH SCH CHC CHC CHC LKY LKY LKY LKY LKY
Weather type....RW RW RW RW RW RW RW RW RW RW RW RW
Tstm cov........ CHC CHC CHC CHC CHC CHC
CWR.............0 0 0 0 0 0 60 60 60 60 60 60
Chc of pcpn (%).30 20 20 20 30 40 50 60 60 60 60 60
Chc of thdr (%).0 0 0 10 10 10 30 30 30 30 30 30
Temp............43 42 42 43 45 47 50 48 46 45 46 45
RH..............89 91 92 93 85 78 70 77 84 91 89 87
20 FT wind dir..S S SW S SW SW SW SW SW SW SW SW
20 FT wind spd..6 6 6 6 8 9 9 11 6 9 8 7
20 FT wind gust.10 8 8 10 13 14 14 17 10 14 13 11
Ridge wind dir..S S SW S SW SW SW SW SW SW SW SW
Ridge wind spd..10 10 10 15 15 15 15 20 15 15 15 15
Mix hgt (kft)...0.5 0.5 0.5 1.0 2.5 3.0 4.0 4.0 3.0 2.0 2.0 2.0
Transp wind dir.SW SW SW SW SW SW SW SW SW SW SW SW
Transp wind spd.12 12 12 13 15 16 20 20 16 16 15 14
SDspl kt-ft/10003 3 3 10 30 43 71 69 42 29 28 25
.TUESDAY NIGHT...
Sky/weather.........Mostly cloudy (55-65 percent). Chance of rain
showers and slight chance of thunderstorms.
CWR.................14 percent.
Chance of pcpn......50 percent.
Chance of thunder...22 percent.
Min temperature.....Around 38.
Max humidity........87 percent.
Wind (20 ft)........Light winds. Gusts up to 15 mph in the evening
and overnight. Gusty and erratic winds expected
near thunderstorms.
Ridgetop wind.......South 10 to 15 mph.
Mixing height.......1000 ft AGL until 2000.
Transport winds.....Southwest 10 to 15 mph.
Smoke dispersal.....Poor.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........75 60 50 45 40 45 55 55 55 55 55 55
Weather cov.....CHC CHC CHC CHC CHC CHC CHC CHC CHC CHC CHC CHC
Weather type....RW RW RW RW RW RW RW RW RW RW RW RW
Tstm cov........SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH
CWR.............10 10 10 10 10 10 10 10 10 10 10 10
Chc of pcpn (%).50 50 50 50 50 50 40 40 40 40 40 40
Chc of thdr (%).20 20 20 10 10 10 10 10 10 10 10 10
Temp............44 45 43 42 41 40 40 40 40 40 40 39
RH..............85 82 85 87 88 88 88 88 88 88 89 89
20 FT wind dir..SW SW SW SW SW S S S S S S S
20 FT wind spd..6 5 5 5 5 6 6 6 5 5 5 5
20 FT wind gust.12 11 10 10 10 10 10 10 10 8 7 7
Ridge wind dir..SW SW SW SW SW S S S S S S S
Ridge wind spd..15 10 10 10 10 10 10 10 10 10 10 10
Mix hgt (kft)...2.0 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 SW SW S S S S S S S S
Transp wind spd.13 10 10 10 10 12 12 12 10 10 10 10
SDspl kt-ft/100023 9 2 2 2 2 2 2 2 2 2 2
.WEDNESDAY...
Sky/weather.........Mostly sunny (40-50 percent). Slight chance of
rain showers through the day. Slight chance of
thunderstorms in the late morning and
afternoon.
CWR.................0 percent.
Chance of pcpn......20 percent.
Chance of thunder...16 percent.
Max temperature.....Around 52.
Min humidity........56 percent.
Wind (20 ft)........Light winds until 1100, then southwest 6 to 11
mph with gusts to around 16 mph. Gusty and
erratic winds expected near thunderstorms in
the late morning and afternoon.
Ridgetop wind.......Southwest 10 to 15 mph until 1700, then west.
Mixing height.......4500 ft AGL after 1100.
Transport winds.....Southwest 10 to 15 mph.
Smoke dispersal.....Poor until 1000, then increasing to good in the
afternoon after 1200.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........55 50 45 40 40 45 45 45 45 50 40 35
Weather cov.....SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH SCH
Weather type....RW RW RW RW RW RW RW RW RW RW RW RW
Tstm cov........ SCH SCH SCH SCH SCH SCH SCH SCH SCH
CWR.............0 0 0 0 0 0 0 0 0 0 0 0
Chc of pcpn (%).20 20 20 20 20 20 20 20 20 20 20 20
Chc of thdr (%).10 10 10 10 10 10 20 20 20 20 20 20
Temp............39 39 39 40 43 46 49 50 51 51 51 51
RH..............89 89 88 85 80 74 68 64 61 59 57 56
20 FT wind dir..S S S S S SW SW SW SW SW SW W
20 FT wind spd..5 5 5 6 6 7 8 9 9 9 8 7
20 FT wind gust.7 8 10 10 12 14 14 16 16 16 14 14
Ridge wind dir..S S S S S SW SW SW SW SW SW W
Ridge wind spd..10 10 10 10 15 15 15 15 15 15 15 15
Mix hgt (kft)...0.1 0.5 0.5 0.5 2.0 3.0 4.5 4.5 4.5 4.5 4.5 4.0
Transp wind dir.S SW SW SW SW SW SW SW SW SW SW W
Transp wind spd.10 10 10 12 13 14 15 16 16 16 15 15
SDspl kt-ft/10002 3 4 5 20 39 60 64 64 64 56 51
.FORECAST DAYS 3 THROUGH 5...
.THURSDAY...
Mostly clear. Slight chance of showers and thunderstorms. Lows
around 40. Highs in the mid 50s. South winds around 7 mph.
.FRIDAY...
Mostly cloudy with chance of showers and slight chance of
thunderstorms. Lows in the upper 30s. Highs in the upper 40s.
Light winds.
.SATURDAY...
Partly cloudy. Slight chance of showers, thunderstorms and snow
showers. Lows in the mid 30s. Highs in the mid 40s. Light winds.
$$
Forecaster...Rowe
Requested by...Matt Ziegler
Type of request...WILDFIRE
.TAG 2522667.1/RIW
.DELDT 09/29/25
.FormatterVersion 2.0.0
.EMAIL wytdc@firenet.gov