USDA Hardiness Zone 7a
Frost Dates for 81503 — Grand Junction, Colorado
NOAA 1991–2020 normals from Grand Junction WFO, CO (4,826 ft), 5 miles northeast.
Updated
In Grand Junction, the last spring frost (32°F) is around April 14 in half of years and has passed by April 28 in nine years out of ten. The first fall frost comes around October 23, as early as October 11 one year in ten, leaving a typical freeze-free season of 190 days (NOAA, Grand Junction WFO, CO).
- Last spring frost
- April 14
- First fall frost
- October 23
- Growing season
- 190 days
- Hardiness zone
- 7a
50% probability
50% probability
freeze-free, 50%
0 to 5°F (-17.8 to -15.0°C) coldest night
- First snow
- November 14
- Last snow
- March 30
- Winters with snow
- 100%
- Snow per year
- 17.7"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Grand Junction
Half of springs at Grand Junction WFO, CO see their last 32°F night by April 14; only one in ten is past it by April 1, and one in ten still has one after April 28. Planting tender crops after April 20 leaves a 30% risk of a frost on them, after April 22 20%, and after April 28 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 45% of the 110 Colorado stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 23 in half of years, as early as October 11 one year in ten, and holds off past November 6 one year in ten. A hard freeze of 28°F follows 10 days later, around November 2; in spring the one-in-ten date for 28°F is April 18, 10 days before the 32°F one. The freeze-free season lasts 190 days in a typical year, the longest of the 110 Colorado stations; it reaches 210 days one year in ten and falls short of 172 one year in ten. On average 117 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about April 25, and return around October 14. Severe cold of 16°F or below comes every winter, usually between November 28 and February 19.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 12 | Apr 17 | Apr 20 | Apr 23 | Apr 25 | Apr 28 | May 1 | May 3 | May 9 |
| 32°F | Apr 1 | Apr 5 | Apr 8 | Apr 11 | Apr 14 | Apr 17 | Apr 20 | Apr 22 | Apr 28 |
| 28°F | Mar 12 | Mar 18 | Mar 24 | Mar 30 | Apr 2 | Apr 5 | Apr 8 | Apr 13 | Apr 18 |
| 24°F | Feb 25 | Mar 3 | Mar 6 | Mar 9 | Mar 14 | Mar 19 | Mar 23 | Mar 30 | Apr 3 |
| 20°F | Feb 13 | Feb 19 | Feb 22 | Feb 27 | Mar 2 | Mar 5 | Mar 8 | Mar 14 | Mar 20 |
| 16°F | Feb 1 | Feb 7 | Feb 12 | Feb 16 | Feb 19 | Feb 23 | Feb 28 | Mar 4 | Mar 11 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 3 | Oct 6 | Oct 9 | Oct 12 | Oct 14 | Oct 16 | Oct 19 | Oct 22 | Oct 26 |
| 32°F | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 6 |
| 28°F | Oct 19 | Oct 23 | Oct 27 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 |
| 24°F | Oct 26 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 14 | Nov 17 | Nov 20 | Nov 24 |
| 20°F | Nov 5 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 22 | Nov 25 | Nov 28 | Dec 4 |
| 16°F | Nov 12 | Nov 19 | Nov 22 | Nov 25 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 15 |
Freeze probabilities 1991–2020 at Grand Junction WFO, 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 81503 →Compare Grand Junction with another place →
Compared with the next station
The nearest other station, Grand Junction Walker Field, CO, 6 miles northeast of Grand Junction, has a last frost 14 days later (April 28), a first frost 7 days earlier (October 16), a season 19 days shorter.
When it snows in Grand Junction, Colorado
The first measurable snow (0.1 inch or more) in Grand Junction usually arrives around November 14, and the last of the season around March 30. Those are the middle dates across the winters of 1991–2020 at Grand Junction Walker Field, CO, 5.7 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 15 days after the last snow.
Planting calendar for 81503
| When | What to do |
|---|---|
| February 3 – February 17 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 17 – March 3 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 17 – March 31 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 14 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 31 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 9 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 23 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 81503 is 5 miles from Grand Junction WFO, CO, which stands at 4,826 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 81504 (Grand Junction). The 2023 USDA Plant Hardiness Zone Map lists ZIP 81503 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°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.