USDA Hardiness Zone 5b
Frost Dates for 81657 — Vail, Colorado
NOAA 1991–2020 normals from Vail, CO (8,304 ft), 1 miles east.
Updated
In Vail, the last spring frost (32°F) is around June 21 in half of years and has passed by July 9 in nine years out of ten. The first fall frost comes around September 7, as early as August 26 one year in ten, leaving a typical freeze-free season of 77 days (NOAA, Vail, CO).
- Last spring frost
- June 21
- First fall frost
- September 7
- Growing season
- 77 days
- Hardiness zone
- 5b
50% probability
50% probability
freeze-free, 50%
-15 to -10°F (-26.1 to -23.3°C) coldest night
- First snow
- October 8
- Last snow
- May 24
- Winters with snow
- 100%
- Snow per year
- 189.2"
median, 1991–2020
median, 1991–2020
22 of 22 observed
NOAA normal
Frost risk by date in Vail
Half of springs at Vail, CO see their last 32°F night by June 21; only one in ten is past it by June 8, and one in ten still has one after July 9. Planting tender crops after June 28 leaves a 30% risk of a frost on them, after July 2 20%, and after July 9 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 89% of the 110 Colorado stations behind this site's ZIP pages.
In fall the first 32°F night comes by September 7 in half of years, as early as August 26 one year in ten, and holds off past September 20 one year in ten. A hard freeze of 28°F follows 14 days later, around September 21; in spring the one-in-ten date for 28°F is June 18, 21 days before the 32°F one. The freeze-free season lasts 77 days in a typical year, shorter than at 98% of the 110 Colorado stations; it reaches 95 days one year in ten and falls short of 53 one year in ten. On average 248 nights a year drop to 32°F or below. Severe cold of 16°F or below comes every winter, usually between October 24 and April 14.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | too rare for a date | ||||||||
| 32°F | Jun 8 | Jun 12 | Jun 15 | Jun 18 | Jun 21 | Jun 24 | Jun 28 | Jul 2 | Jul 9 |
| 28°F | May 16 | May 21 | May 25 | May 29 | May 31 | Jun 3 | Jun 7 | Jun 11 | Jun 18 |
| 24°F | Apr 27 | May 1 | May 4 | May 7 | May 10 | May 13 | May 17 | May 20 | May 25 |
| 20°F | Apr 13 | Apr 17 | Apr 21 | Apr 24 | Apr 28 | Apr 30 | May 3 | May 6 | May 11 |
| 16°F | Mar 31 | Apr 4 | Apr 7 | Apr 11 | Apr 14 | Apr 18 | Apr 21 | Apr 26 | May 1 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | too rare for a date | ||||||||
| 32°F | Aug 26 | Sep 1 | Sep 3 | Sep 5 | Sep 7 | Sep 10 | Sep 13 | Sep 16 | Sep 20 |
| 28°F | Sep 7 | Sep 12 | Sep 15 | Sep 18 | Sep 21 | Sep 23 | Sep 26 | Sep 29 | Oct 2 |
| 24°F | Sep 20 | Sep 25 | Sep 28 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 11 | Oct 15 |
| 20°F | Oct 1 | Oct 5 | Oct 8 | Oct 12 | Oct 15 | Oct 17 | Oct 19 | Oct 22 | Oct 28 |
| 16°F | Oct 10 | Oct 14 | Oct 17 | Oct 20 | Oct 24 | Oct 27 | Oct 31 | Nov 2 | Nov 7 |
Freeze probabilities 1991–2020 at Vail, CO, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 81657 →Compare Vail with another place →
Weather by month in Vail
July is the warmest month at Vail, CO, averaging 77°F by day and 42°F at night; January is the coldest at 29°F and 7°F. A freezing night is all but certain in every month from September to June (a 90% chance or more). No month is safe from a 32°F night: even the warmest has at least a 10% chance. In spring, July still brings one in 22% of years.
Warmth for growing adds up to 744 growing degree days a year (base 50°F), fewer than at 95% of the 110 Colorado stations. 21% of them (157) have built up by the end of June, and July adds the most, 285. Precipitation totals 22.5 inches a year, most in April (2.4") and least in June (1.2"); May to September bring 39% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 29 | 7 | 2.0 | 100% | 31 | 0 |
| Feb | 33 | 9 | 2.0 | 100% | 28 | 0 |
| Mar | 42 | 17 | 1.8 | 100% | 31 | 0 |
| Apr | 49 | 24 | 2.4 | 100% | 28 | 1 |
| May | 60 | 31 | 2.0 | 100% | 21 | 26 |
| Jun | 71 | 36 | 1.2 | 98% | 7 | 130 |
| Jul | 77 | 42 | 1.8 | 22% | 1 | 285 |
| Aug | 74 | 41 | 1.8 | 20% | <1 | 232 |
| Sep | 67 | 34 | 2.0 | 98% | 12 | 68 |
| Oct | 54 | 25 | 1.8 | 100% | 28 | 3 |
| Nov | 38 | 15 | 2.0 | 100% | 30 | 0 |
| Dec | 28 | 7 | 1.7 | 100% | 31 | 0 |
Monthly normals 1991–2020 at Vail, CO (8,304 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Kremmling, CO, 29 miles north of Vail and 844 feet lower, has a last frost 7 days earlier (June 14), a first frost 2 days earlier (September 5), a season 3 days longer.
When it snows in Vail, Colorado
The first measurable snow (0.1 inch or more) in Vail usually arrives around October 8, and the last of the season around May 24. Those are the middle dates across the winters of 1991–2020 at Vail, CO, 1 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 28 days after the last snow.
Planting calendar for 81657
| When | What to do |
|---|---|
| April 12 – April 26 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| April 26 – May 10 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| May 24 – June 7 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| June 21 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by June 15 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by August 24 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| September 7 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 81657 is 1 mile from Vail, CO, which stands at 8,304 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 80924 (Colorado Springs). The 2023 USDA Plant Hardiness Zone Map lists ZIP 81657 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.