When is the last frost in Shawnee, CO?

For ZIP code 80475, the average last spring frost (32°F) is June 16, based on NOAA 1991-2020 climate normals for the Bailey, CO weather station. There is a 1-in-10 chance of a frost after July 1.

When is the first frost in Shawnee, CO?

The average first fall frost (32°F) is September 8. There is a 1-in-10 chance of frost by August 27, so tender plants are at risk from that point on.

How long is the growing season in 80475?

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 80475Shawnee, CO

The average last spring frost in Shawnee is June 16 and the average first fall frost is September 8, giving a typical growing season of about 84 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost: Jun 16
Average first fall frost: Sep 8
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)	—	—	56 days	100%
Frost / freeze (32°F)	Jun 2 · Jun 16 · Jul 1	Aug 27 · Sep 8 · Sep 20	84 days	100%
Hard freeze (28°F)	May 14 · May 30 · Jun 15	Sep 6 · Sep 19 · Oct 1	111 days	100%

Where these dates come from

ZIP code 80475 is matched to the NOAA station Bailey, CO, 6.9 km away, at 7,752 ft elevation (368 ft lower than the ZIP code's center). Nearby stations for comparison:

Station	Elevation	Avg last frost	Avg first frost
Bailey, CO (used)	7,752 ft	Jun 16	Sep 8
Grant, CO	8,675 ft	Jun 15	Sep 9
Cabin Creek, CO	10,021 ft	Jun 6	Sep 19
Evergreen, CO	6,985 ft	May 23	Sep 22

Frost dates near Shawnee

Bailey, CO 80421 · last Jun 15, first Sep 9
Grant, CO 80448 · last Jun 15, first Sep 9
Pine, CO 80470 · last Jun 16, first Sep 8
Jefferson, CO 80456 · last Jun 15, first Sep 9
Conifer, CO 80433 · last Jun 15, first Sep 9
Buffalo Creek, CO 80425 · last May 17, first Oct 1
Evergreen, CO 80439 · last May 23, first Sep 22
Littleton, CO 80162 · last Jun 16, first Sep 8

Frequently asked questions

When is the last frost in Shawnee, CO?: For ZIP code 80475, the average last spring frost (32°F) is June 16, based on NOAA 1991-2020 climate normals for the Bailey, CO weather station. There is a 1-in-10 chance of a frost after July 1.
When is the first frost in Shawnee, CO?: The average first fall frost (32°F) is September 8. There is a 1-in-10 chance of frost by August 27, so tender plants are at risk from that point on.
How long is the growing season in 80475?: 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.