When is the last frost in Moore, ID?

For ZIP code 83255, the average last spring frost (32°F) is June 14, based on NOAA 1991-2020 climate normals for the Chilly Barton Flat, ID weather station. There is a 1-in-10 chance of a frost after June 30.

When is the first frost in Moore, ID?

The average first fall frost (32°F) is September 8. There is a 1-in-10 chance of frost by August 26, so tender plants are at risk from that point on.

How long is the growing season in 83255?

In half of years, the frost-free season (between the last and first 32°F frost) is at least 86 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 83255Moore, ID

The average last spring frost in Moore is June 14 and the average first fall frost is September 8, giving a typical growing season of about 86 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jun 14
Average first fall frost: Sep 8
Growing season: 86 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 27 · Jun 14 · Jun 30	Aug 26 · Sep 8 · Sep 22	86 days	100%
Hard freeze (28°F)	May 7 · May 24 · Jun 15	Sep 5 · Sep 20 · Oct 4	118 days	100%

Where these dates come from

ZIP code 83255 is matched to the NOAA station Chilly Barton Flat, ID, 40.8 km away, at 6,260 ft elevation (1,821 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Chilly Barton Flat, ID (used)	6,260 ft	Jun 14	Sep 8
Arco, ID	5,325 ft	May 22	Sep 22
Mackay Lost Rvr Rs, ID	5,897 ft	Jun 1	Sep 20
Arco 17 Sw, ID	5,920 ft	May 24	Oct 1

Frost dates near Moore

Arco, ID 83213 · last May 22, first Sep 22
Mackay, ID 83251 · last Jun 1, first Sep 20
Howe, ID 83244 · last May 24, first Sep 14
Atomic City, ID 83215 · last Jun 11, first Sep 6
Carey, ID 83320 · last Jun 16, first Sep 9
Picabo, ID 83348 · last Jun 16, first Sep 9
Sun Valley, ID 83353 · last —, first —
Bellevue, ID 83313 · last May 13, first Oct 2

Frequently asked questions

When is the last frost in Moore, ID?: For ZIP code 83255, the average last spring frost (32°F) is June 14, based on NOAA 1991-2020 climate normals for the Chilly Barton Flat, ID weather station. There is a 1-in-10 chance of a frost after June 30.
When is the first frost in Moore, ID?: The average first fall frost (32°F) is September 8. There is a 1-in-10 chance of frost by August 26, so tender plants are at risk from that point on.
How long is the growing season in 83255?: In half of years, the frost-free season (between the last and first 32°F frost) is at least 86 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.