Marine Weather and Tide Forecast for Big Sky, MT

DISCUSSION
/Issued 309 PM MDT Tue Oct 14 2025/

- Meteorological Overview: Scattered showers continue to push northward through the CWA this afternoon. A few isolated thunderstorms are trying to move into the West Yellowstone area as well. Overall, precip diminishes this evening, with the potential for patchy fog later tonight. However, cloud cover will limit the coverage area.

For Wednesday, another round of showers and mountain snow develops. Snow levels will be rather high, above 7000 feet in most areas.

Afternoon temperatures will continue a very slow warming trend over the next few days, but likely to average a bit below normal until Sunday. Additionally, the next upper level low from the west moves into the western portions of the CWA by Sun/Mon...increasing the chances for precipitation.

- Forecast Confidence & Scenarios: Overall, precipitation is light tonight
For Wed/Thu
the heaviest snowfall is expected in the mountains around and just east of Big Sky. Snow accumulations of 2 to 4 inches is possible, mostly above 7000 feet. Since most/all of the snow is expected above pass level with this event, no advisory will be issued at this time.

For Sunday, the GFS/EC have different solutions on the timing of the next weather system. The EC is much quicker, thus cooler temperatures on Sunday. The GFS is warmer/drier on Sunday, with the potential for afternoon temperatures above 70 degrees. With confidence low on either solution at this time, the blend of the NBM is on track. Brusda

AVIATION
15/00Z TAF Period

MVFR clouds hand around in the early evening. There may be some breaks in MVFR ceilings tonight before patchy fog/precipitation reintroduces them early Wednesday morning. Confidence for fog affecting terminals across North Central MT is not high at the moment, but guidance suggest terminals will go down to IFR condtions if it does set up. The next wave of precipitation look to bring IFR ceilings at times again Wednesday morning. Snow/rain and snow mix will impact Southwest MT in the morning before switching to rain in the afternoon. Mountain obscuration persists due to lower clouds and precipitation. -Wilson

PRELIMINARY POINT TEMPS/POPS
GTF 27 47 35 53 / 10 30 60 50 CTB 22 49 31 58 / 0 10 20 10 HLN 28 50 35 53 / 20 50 60 60 BZN 29 50 33 47 / 50 60 70 80 WYS 28 50 28 44 / 80 90 80 90 DLN 31 48 33 50 / 40 60 60 50 HVR 25 49 35 55 / 10 50 60 50 LWT 27 49 33 45 / 40 60 70 80

TFX WATCHES/WARNINGS/ADVISORIES
None.