When is the last frost in West Yellowstone, MT?

Frost is possible in any month at the nearest NOAA station (W Yellowstone Gateway, MT), so there is no reliable average last frost date.

When is the first frost in West Yellowstone, MT?

Frost is possible in any month at the nearest NOAA station.

Are these frost dates a forecast?

No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.

Frost dates for 59758West Yellowstone, MT

Frost is possible in any month near West Yellowstone, based on NOAA 1991-2020 records for the W Yellowstone Gateway, MT station.

Frost is possible in any month. Even summer nights can drop to freezing at this station, so protect tender plants whenever cold nights are forecast.

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
Temperature	Last spring: 90% / 50% / 10% chance	First fall: 10% / 50% / 90% chance	Growing season (50%)	Years with at least one
Light frost (36°F)	—	—	16 days	100%
Frost / freeze (32°F)	—	—	33 days	100%
Hard freeze (28°F)	—	—	62 days	100%

Where these dates come from

ZIP code 59758 is matched to the NOAA station W Yellowstone Gateway, MT, 1.2 km away, at 6,679 ft elevation (12 ft higher than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
W Yellowstone Gateway, MT (used)	6,679 ft	—	—
Hebgen Dam, MT	6,489 ft	Jun 15	Sep 10
Old Faithful, WY	7,351 ft	—	—
Island Park, ID	6,290 ft	—	—

Frost dates near West Yellowstone

Island Park, ID 83429 · last —, first —
Yellowstone National Park, WY 82190 · last —, first —
Macks Inn, ID 83433 · last —, first —
Gardiner, MT 59030 · last —, first —
Cameron, MT 59720 · last Jun 4, first Sep 18
Emigrant, MT 59027 · last May 21, first Sep 27
Big Sky, MT 59716 · last —, first —
Gallatin Gateway, MT 59730 · last —, first —

Frequently asked questions

When is the last frost in West Yellowstone, MT?: Frost is possible in any month at the nearest NOAA station (W Yellowstone Gateway, MT), so there is no reliable average last frost date.
When is the first frost in West Yellowstone, MT?: Frost is possible in any month at the nearest NOAA station.
Are these frost dates a forecast?: No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.