Big Sky 7-Day Snow Forecast

Big Sky Long-Range Snow Forecast Updated today

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Updated 18 September 2026 15:47 AEST

Long-Range Snow Forecast for Big Sky

Long-range (14 to 45 days) from 18 September.

For Forecast detail, see below.

Big Sky Snow Forecast Highlights

When will there be fresh snow in Big Sky?

Big Sky Snow Forecast Highlights - GFS
Snowfall prediction at mid-mountain (2,740m)
Next Snow Expected	2 October
Next Snow Amount	2cm
Next 48 Hours	-
Next 7 Days	-

Long-range Snow Outlook for Big Sky

Snowfall

Snow Line

Max 23℃
Min 6℃

1cm New Snow

Snow Line from 3,229m to 3,159m, with rain below.

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Big Sky Long-Range (2 weeks+) Snow Forecast Outlook

Note :- Mountain weather is extremely dynamic; the forecast below will change. Any forecast snow may move forward or back in the forecast, and predicted snowfall depths will be revised in subsequent updates.

16 Day Weather and Snow Forecast for Big Sky from OpenMeteo(GFS)
	Snow and Weather	Temp Town
Fri 18	Cloudy.	Max 21℃ Min 8℃
Sat 19	Cloudy.	Max 12℃ Min 8℃
Sun 20	Cloudy.	Max 15℃ Min 8℃
Mon 21	Clear sky.	Max 19℃ Min 6℃
Tue 22	Cloudy.	Max 20℃ Min 8℃
Wed 23	Clear sky.	Max 21℃ Min 8℃
Thu 24	Clear sky.	Max 23℃ Min 9℃

This Snow Forecast for Big Sky, United States gives the predicted Snowfall and Freezing Levels for the next week.

The forecast snowfall depths given are the likely average accumulations for the Lower and Upper slopes. The actual snow depth in Big Sky, on any given trail or itinerary, may be dramatically different, particularly if the snowfall is accompanied by high winds and/or varying air temperatures.

Snow Forecasts beyond two days ahead are subject to significant change and variable reliability.

Big Sky Snow Forecast updated at 15:47 AEST, next update expected imminently.

Ensemble forecast for Big Sky, USA at 2,070m

Daily Mean Temperature (yellow line is control)

Daily Total Precipitation (blue line is control)

What are Forecast Ensembles ? Multiple forecasts from running the same weather model with slightly different inputs. The prominent line (the 'control') is the model output from standard inputs, the thinner lines are the variations. Plotted together, they show a range of possible outcomes; the closer they are, the higher the confidence.

How to read Long Range Ensemble Forecasts

These forecasts are from ECMWF EC46, a long-range, low-resolution (area) model. They may not accurately reflect local conditions and should be read as area forecasts, indicating whether the coming weeks are likely to be warmer, colder, wetter, or drier than average.

What to look for?

Temperatures trending downward at the same time as precipitation spikes upward... means snow!

Lines close together indicate a high confidence, while wider spreads signal uncertainty.

Snow Reliability

Big Sky enjoys reliable snow conditions, with an average annual snowfall of over 400 inches. Skiers can expect a solid snow depth throughout the season, but it's advisable to check J2Ski for the latest snow conditions.

Off-Piste Safety in Big Sky

Before skiing or snowboarding off-piste in Big Sky, you must assess the local snow conditions. Always check the local Avalanche Risk Level and ski with appropriate safety equipment.