Spot Forecast
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
443
FNUS75 KTFX 211203
FWSTFX
Spot Forecast for Rugby...HIDC
National Weather Service Great Falls MT
603 AM MDT Fri Aug 21 2026
Forecast is based on forecast start time of 0600 MDT on August 21.
If conditions become unrepresentative...contact the National Weather
Service.
.DISCUSSION...
Warm and dry conditions continue today with increasing higher
level clouds late in the day. A subtle shortwave embedded in an
increasingly southwesterly flow aloft will send a wave of
weakening isolated showers and thunderstorms into the Little Belts
late tonight into Saturday morning. The primary concern with this
activity will be wind gusts in excess of 25 mph and isolated
lightning. More impactful storms will move through late Saturday
afternoon and evening. Wind gusts with these may exceed 60 mph
with the strongest cores in addition to brief heavy downpours,
hail, and cloud to ground lightning. Another round of storms may
move through on Sunday, though this is contingent on the timing of
the surface front. Otherwise, Sunday will be breezy and dry with
localized elevated fire weather.
.TODAY...
Sky/weather.........Mostly sunny (25-35 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Max temperature.....78-83.
Min humidity........22-26 percent.
Wind (20 ft)........
Slope/valley.......Northerly winds around 5 to 10 mph.
Ridgetop...........Northwesterly around 5 to 15 mph.
Mixing height.......5500 ft AGL.
Transport winds.....Northwest 5 to 10 mph.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........40 45 28 18 20 22 24 11 15 19 22 19
Weather cov.....PTY PTY PTY PTY PTY
Weather type....SMK SMK SMK SMK SMK
Tstm cov........
CWR.............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............59 57 59 63 68 72 74 77 78 79 80 79
RH..............41 44 49 47 43 41 39 37 30 28 25 24
20 FT wind dir..N N NW NW W NW NW NW NW NW N N
20 FT wind spd..5 0 0 0 0 5 5 5 5 5 5 5
20 FT wind gust. 5 5 5 5 10 10 10 10 10 10
Ridge wind dir..NW NW W W W W W W W W NW N
Ridge wind spd..5 5 5 5 5 5 5 5 5 5 5 5
Mix hgt (kft)...0.5 0.5 0.5 0.5 1.0 2.5 3.5 4.5 5.0 5.5 5.5 5.0
Transp wind dir.NW NW N NW NW NW NW W W W NW N
Transp wind spd.5 5 5 5 5 5 5 5 5 5 10 10
.TONIGHT...
Sky/weather.........Becoming mostly cloudy (70-80 percent). Slight chance of
showers and thunderstorms after 3 am.
CWR.................5 percent.
Chance of thunder...15 percent.
Min temperature.....58-63.
Max humidity........51-56 percent.
Wind (20 ft)........
Slope/valley.......Easterly winds 5 to 15 mph. Gusty and
erratic winds expected near showers or thunderstorms
Ridgetop...........Easterly 5 to 15 mph.
Mixing height.......500 ft AGL.
Transport winds.....Easterly around 10 to 15 mph
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........25 27 52 61 71 63 60 56 66 47 60 91
Weather cov..... SCH SCH
Weather type.... RW RW
Tstm cov........ SCH SCH
CWR.............0 0 0 0 0 0 10 10 10 10 10 10
Chc of thdr (%).0 0 0 0 0 0 0 10 10 10 20 20
Temp............79 78 73 69 67 66 65 64 64 63 62 62
RH..............33 36 42 46 46 47 46 46 47 48 48 49
20 FT wind dir..N NE NE E E SE SE SE SE SE SE SE
20 FT wind spd..5 5 5 10 5 5 10 10 10 10 10 10
20 FT wind gust.10 15 15 15 15 20 20 20 20 20 15
Ridge wind dir..NE NE E SE SE SE SE SE S S S S
Ridge wind spd..5 5 5 10 10 15 15 15 15 15 15 15
Mix hgt (kft)...4.0 2.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
Transp wind dir.NE E NE E E SE SE SE SE SE SE S
Transp wind spd.10 10 10 10 10 10 15 15 15 15 15 15
.SATURDAY...
Sky/weather.........Cloudy (85-95 percent) then becoming partly
sunny (30-50 percent). Slight chance of showers
and thunderstorms in the morning. Slight chance
of showers and thunderstorms in the
afternoon.
CWR.................5 percent.
Chance of thunder...20 percent.
Max temperature.....78-83.
Min humidity........20-25 percent.
Wind (20 ft)........
Slope/valley.......Southeast winds 5 to 10 mph shifting to the
southwest in the afternoon. Gusty and erratic
winds expected near thunderstorms in the
morning. Gusty and erratic winds expected near
thunderstorms late in the afternoon.
Ridgetop...........Southwest 15 to 20 mph shifting to the west
around 10 mph late in the afternoon.
Mixing height.......6500 ft AGL.
Transport winds.....South 10 to 15 mph shifting to the west late in
the afternoon.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........100 100 100 92 92 92 79 79 79 35 35 35
Weather cov.....SCH SCH SCH SCH SCH SCH SCH SCH
Weather type....RW RW RW RW RW RW RW RW
Tstm cov........SCH SCH SCH SCH SCH SCH SCH SCH
CWR.............10 10 10 10 10 10 10 10 10 10 10 10
Chc of thdr (%).20 20 20 20 20 20 20 10 10 10 10 20
Temp............62 60 61 63 68 71 73 76 78 78 80 78
RH..............49 55 56 56 48 45 41 38 30 28 25 22
20 FT wind dir..SE SE SE S S S S S S SW SW SW
20 FT wind spd..10 5 5 5 5 5 10 10 10 5 5 5
20 FT wind gust.15 15 15 15 15 20 20 20 20 25 25 25
Ridge wind dir..S S SW SW SW S S S SW SW SW W
Ridge wind spd..15 20 20 20 20 20 20 20 20 25 20 20
Mix hgt (kft)...0.5 0.5 0.5 1.0 1.5 1.5 2.5 5.5 5.5 6.0 6.5 5.5
Transp wind dir.S SE S S S S S S S SW SW W
Transp wind spd.15 10 10 10 15 15 15 15 20 15 10 10
$$
Forecaster...Greely
Requested by...RCH
Type of request...WILDFIRE
.TAG 2620058.1/TFX
.DELDT 08/21/26
.FormatterVersion 2.0.0
.EMAIL xavier.delatorre@usda.gov,mthdc@firenet.gov,Ryan.Kooiker@usda.gov,claybus2481@gmail.com,
tfx.ops@noaa.gov