When is the last frost in Lyman, WY?

For ZIP code 82937, the average last spring frost (32°F) is June 14, based on NOAA 1991-2020 climate normals for the Mtn View, WY weather station. There is a 1-in-10 chance of a frost after July 1.

When is the first frost in Lyman, WY?

The average first fall frost (32°F) is September 9. There is a 1-in-10 chance of frost by August 23, so tender plants are at risk from that point on.

How long is the growing season in 82937?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 84 days long.

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 82937Lyman, WY

The average last spring frost in Lyman is June 14 and the average first fall frost is September 9, giving a typical growing season of about 84 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jun 14
Average first fall frost: Sep 9
Growing season: 84 days

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)	—	—	60 days	100%
Frost / freeze (32°F)	May 31 · Jun 14 · Jul 1	Aug 23 · Sep 9 · Sep 21	84 days	100%
Hard freeze (28°F)	May 15 · May 30 · Jun 17	Sep 5 · Sep 20 · Oct 1	109 days	100%

Where these dates come from

ZIP code 82937 is matched to the NOAA station Mtn View, WY, 8 km away, at 6,800 ft elevation (94 ft higher than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Mtn View, WY (used)	6,800 ft	Jun 14	Sep 9
Church Buttes Gas Plt, WY	7,079 ft	May 25	Sep 27
Evanston 1 E, WY	6,825 ft	Jun 12	Sep 12
Kemmerer 2N, WY	6,937 ft	—	—

Frost dates near Lyman

Fort Bridger, WY 82933 · last Jun 14, first Sep 9
Mountain View, WY 82939 · last Jun 14, first Sep 9
Robertson, WY 82944 · last Jun 11, first Sep 18
Lonetree, WY 82936 · last May 25, first Sep 27
Granger, WY 82934 · last May 24, first Sep 22
Little America, WY 82929 · last May 24, first Sep 22
Mc Kinnon, WY 82938 · last May 22, first Sep 29
Opal, WY 83124 · last —, first —

Frequently asked questions

When is the last frost in Lyman, WY?: For ZIP code 82937, the average last spring frost (32°F) is June 14, based on NOAA 1991-2020 climate normals for the Mtn View, WY weather station. There is a 1-in-10 chance of a frost after July 1.
When is the first frost in Lyman, WY?: The average first fall frost (32°F) is September 9. There is a 1-in-10 chance of frost by August 23, so tender plants are at risk from that point on.
How long is the growing season in 82937?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 84 days long.
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.