871
FNUS75 KTFX 290050
FWSTFX
SPOT FORECAST FOR TWIN SISTERS FIRE...USFS
NATIONAL WEATHER SERVICE GREAT FALLS MT
650 PM MDT TUE JUL 28 2026
FORECAST IS BASED ON FORECAST START TIME OF 1900 MDT ON JULY 28.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.
DISCUSSION
THE UPPER LEVEL RIDGE WILL CONTINUE VERY WARM TEMPERATURES THROUGH
THE WEEK, WITH THE HOTTEST TEMPERATURES SETTLING IN DURING THE
WEEKEND. THERE IS AN ISOLATED CHANCE FOR A FEW SHOWERS AND
THUNDERSTORMS EACH AFTERNOON AND EVENING THROUGH FRIDAY. FOR THE
EVENING, BEST WINDOW FOR SHOWERS WILL BE BE BETWEEN 2100-000
GUSTY WINDS WILL BE THE PRIMARY CONCERN WITH STORMS. POORER
OVERNIGHT HUMIDITIES PERSIST THROUGH THE WEEK.
REST OF TONIGHT
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT). SLIGHT CHANCE OF
SHOWERS EARLY IN THE EVENING. PATCHY SMOKE IN
THE EVENING AND OVERNIGHT. AREAS OF SMOKE AFTER
3 AM.
CWR.................5 PERCENT.
CHANCE OF THUNDER...10 PERCENT.
MIN TEMPERATURE.....59-64.
MAX HUMIDITY........37-42 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......DOWNSLOPE WINDS UP TO 8 MPH.
RIDGETOP...........SOUTHEAST 5 TO 10 MPH DECREASING TO 0 TO 5 MPH
LATE IN THE EVENING, THEN INCREASING TO 10 TO
15 MPH OVERNIGHT SHIFTING TO THE NORTHEAST.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....SOUTH AROUND 10 MPH SHIFTING TO THE NORTHWEST
IN THE LATE EVENING AND OVERNIGHT.
TIME (MDT) 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........30 30 16 9 7 21 25 19 17 8 12
WEATHER COV.....SCH SCH PTY PTY PTY PTY PTY PTY ARS ARS ARS
WEATHER TYPE....RW RW SMK SMK SMK SMK SMK SMK SMK SMK SMK
TSTM COV........
CWR.............10 10 10 10 10 0 0 0 0 0 0
CHC OF THDR (%).10 10 0 0 0 0 0 0 0 0 0
TEMP............84 81 73 71 69 68 69 68 65 64 64
RH..............27 34 39 41 41 42 40 41 43 43 41
20 FT WIND DIR..SW W SW SW SW SW SW SW W W NW
20 FT WIND SPD..5 5 5 5 5 5 5 5 5 5 5
20 FT WIND GUST.15 15 15 10 10 10 10 10 10 10 10
RIDGE WIND DIR..S SE SE SE SE E SE SE S SE NE
RIDGE WIND SPD..10 5 5 5 0 5 5 10 15 10 5
MIX HGT (KFT)...5.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
TRANSP WIND DIR.S S S W W NW NW NW NW N N
TRANSP WIND SPD.10 10 10 10 10 10 5 5 5 10 10
WEDNESDAY
SKY/WEATHER.........MOSTLY SUNNY (25-35 PERCENT). AREAS OF SMOKE
EARLY IN THE MORNING, THEN PATCHY SMOKE.
CWR.................5 PERCENT.
CHANCE OF THUNDER...10 PERCENT.
MAX TEMPERATURE.....84-89.
MIN HUMIDITY........17-22 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......NORTHWEST WINDS 10 TO 15 MPH SHIFTING TO THE
NORTHEAST EARLY IN THE AFTERNOON, THEN SHIFTING
TO THE SOUTH LATE IN THE AFTERNOON.
RIDGETOP...........LIGHT AND VARIABLE IN THE MORNING, BECOMING
10 TO 15 MPH WEST IN THE AFTERNOON, SHIFTING
TO THE SOUTH LATE IN THE AFTERNOON.
MIXING HEIGHT.......6000 FT AGL.
TRANSPORT WINDS.....NORTH 10 TO 15 MPH SHIFTING TO THE SOUTHWEST
LATE IN THE AFTERNOON.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........10 14 8 8 11 19 27 46 53 43 43 40
WEATHER COV.....ARS 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 10 10 10 10 10 10
CHC OF THDR (%).0 0 0 0 0 0 0 0 0 10 10 10
TEMP............62 66 69 72 76 78 79 82 84 84 85 84
RH..............40 38 34 30 29 27 26 25 23 22 23 24
20 FT WIND DIR..NW NW NW N N N N N NE NE SE S
20 FT WIND SPD..10 10 10 15 10 10 10 10 10 10 5 5
20 FT WIND GUST.15 15 15 20 20 20 20 20 20 20 15 15
RIDGE WIND DIR..N NW W W W W W W W W SW S
RIDGE WIND SPD..0 0 0 0 5 5 10 10 10 10 15 15
MIX HGT (KFT)...0.5 0.5 1.0 1.5 2.0 2.5 3.0 4.0 5.0 6.0 6.0 4.5
TRANSP WIND DIR.N N N N N N N W W SW SW SW
TRANSP WIND SPD.10 10 10 15 10 10 10 10 10 10 10 10
WEDNESDAY NIGHT
SKY/WEATHER.........MOSTLY CLOUDY (60-70 PERCENT) THEN BECOMING
PARTLY CLOUDY (45-55 PERCENT). SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS EARLY IN THE EVENING.
PATCHY SMOKE IN THE EVENING.
CWR.................5 PERCENT.
CHANCE OF THUNDER...15 PERCENT.
MIN TEMPERATURE.....58-63.
MAX HUMIDITY........45-50 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTHEAST WINDS AROUND 5 MPH SHIFTING TO THE
SOUTHWEST IN THE LATE EVENING AND OVERNIGHT.
GUSTY AND ERRATIC WINDS EXPECTED NEAR
THUNDERSTORMS EARLY IN THE EVENING.
RIDGETOP...........SOUTH 10 TO 15 MPH DECREASING TO 5 TO 10 MPH IN
THE LATE EVENING AND OVERNIGHT.
MIXING HEIGHT.......500 FT AGL.
TRANSPORT WINDS.....SOUTHEAST AROUND 10 MPH SHIFTING TO THE
SOUTH OVERNIGHT, THEN SHIFTING TO THE SOUTHWEST
AFTER 3 AM.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........60 60 60 69 69 69 56 56 56 50 50 50
WEATHER COV.....SCH SCH SCH PTY PTY PTY PTY
WEATHER TYPE....RW RW RW SMK SMK SMK SMK
TSTM COV........SCH SCH SCH
CWR.............10 10 10 10 10 10 10 10 10 10 10 10
CHC OF THDR (%).20 20 20 0 0 0 10 0 0 0 0 0
TEMP............82 80 75 71 69 68 67 67 66 64 63 63
RH..............27 32 40 44 45 45 47 45 47 48 50 50
20 FT WIND DIR..SE SE SE SW SW SW 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 S S S S S S S SW S S
RIDGE WIND SPD..15 15 10 5 5 5 5 5 10 10 10 10
MIX HGT (KFT)...3.5 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.SE SE S SW SW S S S S S SW SW
TRANSP WIND SPD.10 10 10 10 10 10 10 10 10 10 10 10
THURSDAY
SKY/WEATHER.........MOSTLY SUNNY (25-35 PERCENT). PATCHY SMOKE
EARLY IN THE MORNING. SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS IN THE AFTERNOON.
CWR.................5 PERCENT.
CHANCE OF THUNDER...20 PERCENT.
MAX TEMPERATURE.....85-90.
MIN HUMIDITY........19-24 PERCENT.
WIND (20 FT)........
SLOPE/VALLEY.......SOUTHWEST WINDS AROUND 10 MPH SHIFTING TO THE
NORTH WITH GUSTS TO AROUND 20 MPH IN THE
AFTERNOON. GUSTY AND ERRATIC WINDS EXPECTED
NEAR THUNDERSTORMS IN THE AFTERNOON.
RIDGETOP...........SOUTHWEST 5 TO 10 MPH SHIFTING TO THE NORTH
LATE IN THE AFTERNOON.
MIXING HEIGHT.......10000 FT AGL.
TRANSPORT WINDS.....WEST AROUND 10 MPH SHIFTING TO THE NORTHWEST
EARLY IN THE MORNING, THEN SHIFTING TO THE
SOUTHWEST LATE IN THE MORNING.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........28 28 28 16 16 16 48 48 48 48 48 48
WEATHER COV.....PTY SCH SCH SCH SCH SCH SCH
WEATHER TYPE....SMK RW RW RW RW RW RW
TSTM COV........ SCH SCH SCH SCH SCH SCH
CWR.............0 0 0 0 0 0 10 10 10 10 10 10
CHC OF THDR (%).0 0 0 0 0 0 20 20 20 20 20 20
TEMP............61 65 68 72 76 79 82 84 84 85 85 85
RH..............50 47 43 38 34 30 27 25 24 24 23 23
20 FT WIND DIR..SW SW SW NW NW NW NE NE NE N N N
20 FT WIND SPD..10 10 10 5 5 5 5 5 5 5 5 5
20 FT WIND GUST. 10 10 10 15 15 15 20 20 20
RIDGE WIND DIR..S SW SW W W W W W W W NW N
RIDGE WIND SPD..10 10 5 5 5 5 5 5 10 10 10 5
MIX HGT (KFT)...0.5 0.5 0.5 1.5 2.5 4.5 6.5 8.0 9.5 10 9.5 8.0
TRANSP WIND DIR.SW W NW N NW SW S S SW SW W W
TRANSP WIND SPD.10 10 10 5 5 5 10 10 10 10 10 10
FORECASTER...WILSON
REQUESTED BY...JAMISON BIRD
TYPE OF REQUEST...WILDFIRE
.TAG 2618336.2/TFX
.DELDT 07/28/26
.FORMATTERVERSION 2.0.0
.EMAIL JAMISON.D.BIRD@USDA.GOV, TFX.OPS@NOAA.GOV
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