055
FNUS75 KTFX 300031
FWSTFX
SPOT FORECAST FOR TWIN SISTERS FIRE...USFS
NATIONAL WEATHER SERVICE GREAT FALLS MT
631 PM MDT WED JUL 29 2026
FORECAST IS BASED ON FORECAST START TIME OF 1900 MDT ON JULY 29.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.
...FIRE WEATHER WATCH IN EFFECT FROM SATURDAY AFTERNOON THROUGH
SUNDAY EVENING...
DISCUSSION
BETWEEN 2300 AND 0100 SHOWERS AND THUNDERSTORMS WILL APPROACH THE
FIRE. TONIGHT AND THURSDAY NIGHT THERE WILL BE MODERATE HUMIDITY
RECOVERY. TOMORROW AND FRIDAY IT WILL BE HOT WITH LIGHT WINDS
AROUND 5 TO 10 MPH WITH GUSTS UP TO 15 MPH. TOMORROW
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS WILL AFFECT THE FIRE.
ALL THUNDERSTORMS WILL PRODUCE FREQUENT LIGHTNING, AND GUSTY,
ERRATIC WINDS.
REST OF TONIGHT
SKY/WEATHER.........MOSTLY CLOUDY (70-80 PERCENT). CHANCE OF SHOWERS
AND SLIGHT CHANCE OF THUNDERSTORMS EARLY IN THE
EVENING, THEN SLIGHT CHANCE OF SHOWERS IN THE
LATE EVENING AND OVERNIGHT.
CWR.................15 PERCENT DECREASING TO 5 PERCENT OVERNIGHT.
CHANCE OF THUNDER...20 PERCENT.
MIN TEMPERATURE.....58-63.
MAX HUMIDITY........47-52 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTHEAST WINDS 5 TO 10 MPH SHIFTING TO THE
SOUTH IN THE LATE EVENING AND OVERNIGHT. GUSTY
AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS
EARLY IN THE EVENING.
RIDGETOP...........SOUTH 5 TO 10 MPH SHIFTING TO THE WEST EARLY IN
THE MORNING.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....SOUTHEAST AROUND 10 MPH SHIFTING TO THE SOUTH
IN THE LATE EVENING AND OVERNIGHT.
TIME (MDT) 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........77 80 83 84 73 75 65 66 69 70 63
WEATHER COV.....CHC CHC SCH SCH SCH SCH SCH SCH
WEATHER TYPE....RW RW RW RW RW RW RW RW
TSTM COV........SCH SCH
CWR.............20 20 20 20 20 10 10 10 10 10 10
CHC OF THDR (%).20 20 10 10 10 0 0 0 0 0 0
TEMP............77 73 69 68 67 66 67 66 64 63 63
RH..............36 43 47 47 47 47 46 47 48 50 51
20 FT WIND DIR..SE S S S S S S S S SW SW
20 FT WIND SPD..10 5 10 10 10 10 10 10 10 10 10
20 FT WIND GUST. 10 15 15 15 15 15 15 15 15 15
RIDGE WIND DIR..SE SE SE S S S S S S SW W
RIDGE WIND SPD..10 10 10 5 5 5 5 5 10 10 10
MIX HGT (KFT)...2.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.SE SE SW SW SW S S S S SW SW
TRANSP WIND SPD.10 10 10 10 10 10 10 10 10 10 10
THURSDAY
SKY/WEATHER.........MOSTLY SUNNY (25-35 PERCENT). SLIGHT CHANCE OF
SHOWERS EARLY IN THE AFTERNOON. SLIGHT CHANCE OF
THUNDERSTORMS EARLY IN THE AFTERNOON. CHANCE OF
SHOWERS EARLY IN THE AFTERNOON.
CWR.................0 PERCENT INCREASING TO 10 PERCENT IN THE
AFTERNOON.
CHANCE OF THUNDER...16 PERCENT.
MAX TEMPERATURE.....84-89.
MIN HUMIDITY........20-25 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......VARIABLE WINDS 5 TO 10 MPH.
GUSTY AND ERRATIC WINDS EXPECTED
NEAR THUNDERSTORMS EARLY IN THE AFTERNOON.
RIDGETOP...........NORTH AROUND 5 MPH SHIFTING TO THE SOUTHEAST
EARLY IN THE MORNING, THEN SHIFTING TO THE
SOUTH LATE IN THE MORNING.
MIXING HEIGHT.......8000 FT AGL.
TRANSPORT WINDS.....WEST 5 TO 10 MPH SHIFTING TO THE NORTHWEST.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........43 35 10 6 19 6 9 45 57 35 40 54
WEATHER COV..... PTY PTY PTY PTY PTY SCH CHC PTY PTY PTY
WEATHER TYPE.... SMK SMK SMK SMK SMK RW RW SMK SMK SMK
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 10 20 20 10 10 10
TEMP............61 65 69 72 77 80 81 82 82 83 83 84
RH..............50 50 46 40 35 32 29 30 28 27 27 26
20 FT WIND DIR..SW SW W N N N NE NE W NE N NW
20 FT WIND SPD..10 5 5 5 5 5 5 5 5 5 5 5
20 FT WIND GUST. 10 10 10 10 15 15 15 15 15 15 15
RIDGE WIND DIR..NW N E SE SE S S S S S S S
RIDGE WIND SPD..5 5 5 5 5 10 10 10 10 10 5 5
MIX HGT (KFT)...0.5 0.5 0.5 2.0 3.5 5.0 7.0 8.0 7.0 7.5 7.5 5.5
TRANSP WIND DIR.SW W W NW NW NW W NW SW W NW W
TRANSP WIND SPD.10 10 5 5 5 5 10 10 10 10 10 10
THURSDAY NIGHT
SKY/WEATHER.........PARTLY CLOUDY (45-55 PERCENT) THEN BECOMING
MOSTLY CLOUDY (75-85 PERCENT). SLIGHT CHANCE OF
SHOWERS IN THE EVENING.
CWR.................5 PERCENT.
CHANCE OF THUNDER...14 PERCENT.
MIN TEMPERATURE.....58-63.
MAX HUMIDITY........45-50 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......EAST WINDS AROUND 5 MPH SHIFTING TO THE
SOUTHWEST IN THE LATE EVENING AND OVERNIGHT.
RIDGETOP...........SOUTH 0 TO 5 MPH INCREASING TO 15 TO 20 MPH
EARLY IN THE EVENING, THEN SHIFTING TO THE
SOUTHWEST AROUND 10 MPH EARLY IN THE MORNING.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....WEST AROUND 10 MPH SHIFTING TO THE NORTHEAST
EARLY IN THE EVENING, THEN SHIFTING TO THE EAST
LATE IN THE EVENING SHIFTING TO THE SOUTHWEST
IN THE LATE EVENING AND OVERNIGHT.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........50 50 50 65 65 65 97 97 97 67 67 67
WEATHER COV.....SCH SCH SCH SCH SCH SCH PTY PTY PTY PTY PTY PTY
WEATHER TYPE....RW RW RW RW RW RW SMK SMK SMK SMK SMK SMK
TSTM COV........
CWR.............10 10 10 10 10 10 10 10 10 10 10 10
CHC OF THDR (%).10 10 10 10 10 10 10 10 10 0 0 0
TEMP............85 81 78 71 69 68 67 67 66 64 63 62
RH..............25 31 39 44 45 46 49 47 48 50 51 51
20 FT WIND DIR..E E E S S S SW SW SW SW SW SW
20 FT WIND SPD..5 5 5 10 10 10 10 10 10 10 10 10
20 FT WIND GUST.15 15 15 15 15 15 15 15 15 15 15 15
RIDGE WIND DIR..S S SE SE SE S S S S SW SW SW
RIDGE WIND SPD..0 5 15 20 20 20 20 20 15 15 15 10
MIX HGT (KFT)...5.0 2.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.W NE E E SW SW SW W W W W W
TRANSP WIND SPD.10 10 5 10 10 10 10 10 10 10 10 10
FRIDAY
SKY/WEATHER.........MOSTLY CLOUDY (65-75 PERCENT) THEN BECOMING
SUNNY (10-20 PERCENT).
CWR.................5 PERCENT.
CHANCE OF THUNDER...9 PERCENT.
MAX TEMPERATURE.....86-91.
MIN HUMIDITY........14-19 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTHWEST WINDS AROUND 10 MPH SHIFTING TO THE
NORTH IN THE AFTERNOON.
RIDGETOP...........WEST 5 TO 10 MPH SHIFTING TO THE NORTHWEST LATE
IN THE AFTERNOON.
MIXING HEIGHT.......9000 FT AGL.
TRANSPORT WINDS.....SOUTHWEST AROUND 10 MPH SHIFTING TO THE
NORTHWEST IN THE LATE MORNING AND AFTERNOON.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........70 70 70 19 19 19 8 8 8 18 18 18
WEATHER COV.....PTY
WEATHER TYPE....SMK
TSTM COV........
CWR.............0 0 0 0 0 0 10 10 10 10 10 10
CHC OF THDR (%).0 0 0 0 0 0 10 10 10 10 10 10
TEMP............61 65 69 73 77 80 83 84 85 86 87 88
RH..............49 47 43 37 32 28 25 24 23 23 21 20
20 FT WIND DIR..SW SW SW W W W N N N N N N
20 FT WIND SPD..10 10 10 5 5 5 5 5 5 10 10 10
20 FT WIND GUST.15 15 15 10 10 10 15 15 15 20 20 20
RIDGE WIND DIR..SW SW SW W W W W W W W NW N
RIDGE WIND SPD..10 10 5 5 5 5 5 5 5 5 5 5
MIX HGT (KFT)...0.5 0.5 0.5 1.5 3.0 5.5 7.5 8.5 9.0 9.0 9.0 8.0
TRANSP WIND DIR.SW SW W W W NW NW NW W W W NW
TRANSP WIND SPD.10 10 10 5 5 10 10 10 10 10 10 10
FORECASTER...GESELL
REQUESTED BY...JAMISON BIRD
TYPE OF REQUEST...WILDFIRE
.TAG 2618336.3/TFX
.DELDT 07/29/26
.FORMATTERVERSION 2.0.0
.EMAIL JAMISON.D.BIRD@USDA.GOV, TFX.OPS@NOAA.GOV
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