443
FNUS75 KTFX 310036
FWSTFX
SPOT FORECAST FOR TWIN SISTERS FIRE...USFS
NATIONAL WEATHER SERVICE GREAT FALLS MT
636 PM MDT THU JUL 30 2026
FORECAST IS BASED ON FORECAST START TIME OF 1900 MDT ON JULY 30.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.
...FIRE WEATHER WATCH IN EFFECT FROM SATURDAY AFTERNOON THROUGH
SUNDAY EVENING...
DISCUSSION
THERE IS A LOW END CHANCE (20% CHANCE) FOR AN ISOLATED SHOWER OR
THUNDERSTORM TO DEVELOP OVER THE FIRE THROUGH 0200 FRIDAY. GUSTY,
ERRATIC WINDS ARE THE MAIN CONCERN WITH THUNDERSTORMS. HOT
TEMPERATURES SETTLE IN FRIDAY AND SATURDAY, WITH POORER OVERNIGHT
HUMIDITIES. A RIDGE BREAKDOWN SATURDAY AND SUNDAY WILL BRING
WINDY, VERY WARM, AND DRY CONDITIONS LEADING TO ELEVATED TO
CRITICAL FIRE WEATHER WITH WIND GUSTS OF 25 TO 30 MPH.
REST OF TONIGHT
SKY/WEATHER.........PARTLY CLOUDY (45-55 PERCENT). SLIGHT CHANCE OF
SHOWERS EARLY IN THE EVENING. CHANCE OF SHOWERS
LATE IN THE EVENING. PATCHY SMOKE THROUGH THE NIGHT.
CWR.................5 PERCENT.
CHANCE OF THUNDER...10 PERCENT.
MIN TEMPERATURE.....59-64.
MAX HUMIDITY........39-44 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......LIGHT DOWNSLOPE WIND BECOMING 10 TO 15 MPH SOUTHWEST
AROUND OVERNIGHT.
RIDGETOP...........NORTHEAST AROUND 10 MPH SHIFTING TO THE
SOUTH LATE IN THE EVENING, SHIFTING TO
THE WEST AFTER 3 AM.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....SOUTH 10 TO 15 MPH.
TIME (MDT) 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........48 48 48 50 48 52 75 80 77 43 32
WEATHER COV.....SCH SCH SCH CHC SCH PTY PTY PTY PTY PTY PTY
WEATHER TYPE....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
CHC OF THDR (%).10 10 10 10 10 0 0 0 0 0 0
TEMP............81 78 71 70 69 68 68 68 66 64 63
RH..............31 38 43 43 44 45 44 46 47 49 48
20 FT WIND DIR..E S S S S SW SW S S SW SW
20 FT WIND SPD..5 5 5 5 10 10 15 10 10 10 10
20 FT WIND GUST.10 10 10 10 15 15 15 15 15 15 15
RIDGE WIND DIR..NE E S S S S S SW W W W
RIDGE WIND SPD..10 10 10 15 15 15 15 15 15 15 15
MIX HGT (KFT)...3.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.S S S S S SW SW SW SW SW SW
TRANSP WIND SPD.10 10 10 10 10 15 15 10 10 10 10
FRIDAY
SKY/WEATHER.........SUNNY (15-25 PERCENT). PATCHY SMOKE.
CWR.................0 PERCENT.
CHANCE OF THUNDER...5 PERCENT.
MAX TEMPERATURE.....86-91.
MIN HUMIDITY........15-20 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTHWEST WINDS 5 TO 10 MPH SHIFTING TO THE
NORTH LATE IN THE MORNING, THEN BECOMING AROUND
5 MPH IN THE AFTERNOON.
RIDGETOP...........NORTHWEST 5 TO 10 MPH BECOMING AROUND 5 MPH
LATE IN THE AFTERNOON.
MIXING HEIGHT.......8500 FT AGL.
TRANSPORT WINDS.....SOUTHWEST 5 TO 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 (%).........24 35 27 23 19 12 7 14 29 22 19 21
WEATHER COV.....PTY PTY PTY PTY PTY PTY PTY PTY PTY PTY PTY PTY
WEATHER TYPE....SMK SMK SMK SMK SMK SMK SMK 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 10 10 0 0
TEMP............62 66 70 73 79 81 83 84 86 86 87 88
RH..............48 46 42 37 31 28 25 25 23 22 21 20
20 FT WIND DIR..SW SW SW NW N N N N NE N N N
20 FT WIND SPD..10 5 5 5 5 5 10 5 5 5 5 5
20 FT WIND GUST. 10 10 10 15 15 15 15 15 15 15 15
RIDGE WIND DIR..W W NW NW NW NW NW NW W W NW NW
RIDGE WIND SPD..10 10 10 10 10 5 5 5 5 5 5 5
MIX HGT (KFT)...0.5 0.5 0.5 1.5 3.5 5.0 6.0 7.5 8.5 8.5 8.5 7.0
TRANSP WIND DIR.SW SW W NW N N NW NW NW NW NW N
TRANSP WIND SPD.10 10 5 5 5 5 10 10 10 10 10 10
FRIDAY NIGHT
SKY/WEATHER.........MOSTLY CLEAR (10-20 PERCENT). AREAS OF SMOKE IN
THE EVENING, THEN PATCHY SMOKE OVERNIGHT.
CWR.................0 PERCENT.
CHANCE OF THUNDER...LESS THAN 5 PERCENT.
MIN TEMPERATURE.....60-65.
MAX HUMIDITY........27-32 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......NORTHEAST WINDS AROUND 5 MPH SHIFTING TO THE
SOUTHWEST IN THE LATE EVENING AND OVERNIGHT.
RIDGETOP...........LIGHT AND VARIABLE, BECOMING TO THE SOUTHEAST 10
TO 15 MPH OVERNIGHT SHIFTING TO THE SOUTH
AROUND 20 MPH EARLY IN THE MORNING.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....NORTH 5 TO 10 MPH SHIFTING TO THE SOUTH
OVERNIGHT.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........18 18 18 11 11 11 22 22 22 21 21 21
WEATHER COV.....ARS ARS ARS ARS ARS ARS PTY PTY PTY PTY PTY PTY
WEATHER TYPE....SMK SMK SMK SMK SMK SMK SMK 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............86 85 81 74 72 70 68 68 68 66 64 64
RH..............21 25 32 35 36 36 39 37 38 39 41 41
20 FT WIND DIR..NE NE NE SW SW SW SW SW SW S S S
20 FT WIND SPD..5 5 5 5 5 5 5 5 5 10 10 10
20 FT WIND GUST.15 15 15 10 10 10 10 10 10 15 15 15
RIDGE WIND DIR..N N NE NE NE E SE SE S S S S
RIDGE WIND SPD..5 5 5 5 5 10 10 15 15 15 15 20
MIX HGT (KFT)...7.0 3.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.N N NE N NW NW S SW S S S S
TRANSP WIND SPD.10 10 5 5 5 5 5 5 5 10 10 10
SATURDAY
SKY/WEATHER.........SUNNY (10-20 PERCENT). PATCHY SMOKE EARLY IN
THE MORNING.
CWR.................0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
MAX TEMPERATURE.....94-99.
MIN HUMIDITY........6-11 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTH WINDS 10 TO 15 MPH.
RIDGETOP...........SOUTHWEST 20 TO 25 MPH SHIFTING TO THE WEST
LATE IN THE AFTERNOON.
MIXING HEIGHT.......10000 FT AGL INCREASING TO 12500 FT AGL LATE IN
THE AFTERNOON.
TRANSPORT WINDS.....SOUTH 10 TO 15 MPH SHIFTING TO THE SOUTHWEST
AROUND 20 MPH IN THE AFTERNOON.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........23 23 23 5 5 5 7 7 7 15 15 15
WEATHER COV.....PTY
WEATHER TYPE....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............63 67 71 75 79 83 87 90 93 94 96 96
RH..............41 39 35 30 26 24 21 18 16 14 12 11
20 FT WIND DIR..S S S S S S S S S SW SW SW
20 FT WIND SPD..10 10 10 10 10 10 15 15 15 15 15 15
20 FT WIND GUST.15 15 15 20 20 20 25 25 25 25 25 25
RIDGE WIND DIR..S S S S S SW SW SW SW W W W
RIDGE WIND SPD..20 20 20 25 25 25 20 25 25 25 25 25
MIX HGT (KFT)...0.5 0.5 1.0 1.5 2.0 3.5 5.0 7.5 10 12 13 13
TRANSP WIND DIR.S S S S S S SW SW SW SW SW SW
TRANSP WIND SPD.10 10 15 15 15 15 15 20 20 20 20 20
FORECASTER...WILSON
REQUESTED BY...JAMISON BIRD
TYPE OF REQUEST...WILDFIRE
.TAG 2618336.4/TFX
.DELDT 07/30/26
.FORMATTERVERSION 2.0.0
.EMAIL HANNAH.PINKERTON@USDA.GOV, TFX.OPS@NOAA.GOV
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