844
FNUS75 KTFX 201638
FWSTFX
SPOT FORECAST FOR LEWIS & CLARK IHC RT-130 FIELD DAY...USFS
NATIONAL WEATHER SERVICE GREAT FALLS MT
1038 AM MDT MON APR 20 2026
FORECAST IS BASED ON FORECAST START TIME OF 1700 MDT ON APRIL 22.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.
..POTENTIAL FOR HEAVY SNOWFALL ON THURSDAY
DISCUSSION
A COLD FRONT WILL MOVE FROM WEST TO EAST ACROSS THE AREA ON
WEDNESDAY AFTERNOON. EXPECT SCATTERED THUNDERSTORMS TO ACCOMPANY
THE FRONTAL PASSAGE. MUCH COOLER TEMPERATURES MOVE INTO THE AREA
WED NIGHT, WITH RAIN CHANGING TO SNOW ON THU MORNING. SOME
FORECAST MODELS HAVE PERIODS OF HEAVY SNOW THROUGHOUT THE DAY
ON THU. EXPECT GUSTY WINDS WITH THE FRONT WED EVENING, WITH
WINDY CONDITIONS CONTINUING INTO THU.
LATE WEDNESDAY AFTERNOON
SKY/WEATHER.........MOSTLY CLOUDY (75-85 PERCENT). SHOWERS
LIKELY, ALONG WITH ISOLATED THUNDERSTORMS.
CHANCE OF PCPN......70 PERCENT.
CHANCE OF LIGHTNING.15 PERCENT.
MAX TEMPERATURE.....60-65.
MIN HUMIDITY........NEAR 30 PERCENT.
SURFACE WINDS (MPH).SOUTHWEST WINDS AROUND 15 MPH WITH GUSTS TO
AROUND 30 MPH.
PCPN AMOUNT.........0.10 INCHES.
SNOWFALL AMOUNT.....0.0 INCHES.
TIME (MDT) 5PM
SKY (%).........82
WEATHER COV.....LKY
WEATHER TYPE....RN
TSTM COV........
CHC OF PCPN (%).70
CHC OF LTNG (%).10
TEMP............54
RH..............40
SURFACE WND DIR.SW
SURFACE WND SPD.15
SURFACE WND GST.30
WEDNESDAY NIGHT
SKY/WEATHER.........CLOUDY (95-100 PERCENT). RAIN SHOWERS, SLIGHT
CHANCE OF THUNDERSTORMS IN THE EVENING.
SNOW AFTER MIDNIGHT.
CHANCE OF PCPN......100 PERCENT.
CHANCE OF LIGHTNING.20 PERCENT.
MIN TEMPERATURE.....NEAR 30.
MAX HUMIDITY........86-91 PERCENT.
SURFACE WINDS (MPH).WEST WINDS AROUND 15 MPH SHIFTING TO THE
NORTHWEST AFTER 3 AM. GUSTS UP TO 35 MPH.
PCPN AMOUNT.........0.84 INCHES.
SNOWFALL AMOUNT.....3 TO 6 INCHES.
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
SKY (%).........98 98 98 98 98 98 100 100 100 100 100 100
WEATHER COV.....DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF
WEATHER TYPE....RW RW RW RS RS RS RS RS RS SN SN SN
TSTM COV........SCH SCH SCH
CHC OF PCPN (%).100 100 100 100 100 100 100 100 100 100 100 100
CHC OF LTNG (%).20 20 20 10 10 10 10 10 10 0 0 0
TEMP............51 48 44 41 39 37 35 34 33 32 30 29
RH..............48 59 72 82 88 90 91 91 90 89 89 88
SURFACE WND DIR.W W W W W W NW NW NW NW NW NW
SURFACE WND SPD.15 15 15 15 15 15 15 15 15 20 20 20
SURFACE WND GST.30 30 30 30 30 30 30 30 30 35 35 35
THURSDAY
SKY/WEATHER.........CLOUDY (90-100 PERCENT). SNOW.
CHANCE OF PCPN......100 PERCENT.
CHANCE OF LIGHTNING.LESS THAN 10 PERCENT.
MAX TEMPERATURE.....30-35.
MIN HUMIDITY........75 PERCENT.
SURFACE WINDS (MPH).NORTHWEST WINDS 15 TO 20 MPH. GUSTS UP TO 40
MPH DECREASING TO 30 MPH IN THE AFTERNOON.
PCPN AMOUNT.........0.50 INCHES.
SNOWFALL AMOUNT.....4 TO 8 INCHES.
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
SKY (%).........98 98 98 98 98 98 94 94 94 94 94 94
WEATHER COV.....DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF DEF
WEATHER TYPE....SN SN SN SN SN SN SN SN SN SN SN SN
TSTM COV........
CHC OF PCPN (%).100 100 100 100 100 100 90 90 90 90 90 90
CHC OF LTNG (%).0 0 0 0 0 0 10 10 10 10 10 10
TEMP............28 27 26 26 27 28 28 29 30 30 30 30
RH..............88 88 87 86 85 84 82 79 76 74 73 73
SURFACE WND DIR.NW NW NW NW NW NW NW NW NW NW NW NW
SURFACE WND SPD.20 20 20 15 15 15 15 15 15 15 15 15
SURFACE WND GST.40 40 40 35 35 35 30 30 30 30 30 30
FORECASTER...BRUSDA
REQUESTED BY...JOEL THOMAS
TYPE OF REQUEST...OTHER
.TAG 2610912.0/TFX
.DELDT 04/20/26
.FORMATTERVERSION 2.0.0
.EMAIL JOEL.THOMAS2@USDA.GOV
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