USDA Hardiness Zone 4a
Frost Dates for 58421 — Carrington, North Dakota
NOAA 1991–2020 normals from Carrington, ND (1,586 ft), 2 miles west.
Updated
In Carrington, the last spring frost (32°F) is around May 10 in half of years and has passed by May 23 in nine years out of ten. The first fall frost comes around September 28, as early as September 17 one year in ten, leaving a typical freeze-free season of 139 days (NOAA, Carrington, ND).
- Last spring frost
- May 10
- First fall frost
- September 28
- Growing season
- 139 days
- Hardiness zone
- 4a
50% probability
50% probability
freeze-free, 50%
-30 to -25°F (-34.4 to -31.7°C) coldest night
- First snow
- November 6
- Last snow
- March 20
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
18 of 18 observed
NOAA normal
Frost risk by date in Carrington
Half of springs at Carrington, ND see their last 32°F night by May 10; only one in ten is past it by April 28, and one in ten still has one after May 23. Planting tender crops after May 15 leaves a 30% risk of a frost on them, after May 18 20%, and after May 23 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 21% of the 33 North Dakota stations behind this site's ZIP pages.
In fall the first 32°F night comes by September 28 in half of years, as early as September 17 one year in ten, and holds off past October 10 one year in ten. A hard freeze of 28°F follows 10 days later, around October 8; in spring the one-in-ten date for 28°F is May 14, 9 days before the 32°F one. The freeze-free season lasts 139 days in a typical year, longer than at 58% of the 33 North Dakota stations; it reaches 157 days one year in ten and falls short of 122 one year in ten. On average 193 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 10 days longer, to about May 20, and return around September 20. Severe cold of 16°F or below comes every winter, usually between November 5 and April 5.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 8 | May 12 | May 15 | May 17 | May 20 | May 22 | May 25 | May 28 | Jun 1 |
| 32°F | Apr 28 | May 2 | May 4 | May 7 | May 10 | May 13 | May 15 | May 18 | May 23 |
| 28°F | Apr 16 | Apr 21 | Apr 25 | Apr 29 | May 1 | May 3 | May 6 | May 10 | May 14 |
| 24°F | Apr 8 | Apr 12 | Apr 15 | Apr 18 | Apr 22 | Apr 24 | Apr 28 | May 1 | May 5 |
| 20°F | Mar 31 | Apr 3 | Apr 6 | Apr 9 | Apr 12 | Apr 15 | Apr 18 | Apr 22 | Apr 28 |
| 16°F | Mar 18 | Mar 25 | Mar 31 | Apr 3 | Apr 5 | Apr 8 | Apr 10 | Apr 14 | Apr 19 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 9 | Sep 13 | Sep 16 | Sep 18 | Sep 20 | Sep 22 | Sep 24 | Sep 26 | Sep 30 |
| 32°F | Sep 17 | Sep 20 | Sep 23 | Sep 26 | Sep 28 | Sep 30 | Oct 3 | Oct 6 | Oct 10 |
| 28°F | Sep 25 | Sep 30 | Oct 3 | Oct 5 | Oct 8 | Oct 10 | Oct 13 | Oct 16 | Oct 21 |
| 24°F | Oct 4 | Oct 9 | Oct 12 | Oct 16 | Oct 18 | Oct 21 | Oct 24 | Oct 26 | Oct 30 |
| 20°F | Oct 15 | Oct 19 | Oct 23 | Oct 26 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 10 |
| 16°F | Oct 24 | Oct 28 | Oct 31 | Nov 3 | Nov 5 | Nov 8 | Nov 10 | Nov 14 | Nov 19 |
Freeze probabilities 1991–2020 at Carrington, ND, 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 58421 →Compare Carrington with another place →
Weather by month in Carrington
July is the warmest month at Carrington, ND, averaging 79°F by day and 57°F at night; January is the coldest at 17°F and 0°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 84% of years.
Warmth for growing adds up to 1,971 growing degree days a year (base 50°F), fewer than at 79% of the 33 North Dakota stations. 31% of them (615) have built up by the end of June, and July adds the most, 561.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 17 | 0 | 100% | 31 | 0 |
| Feb | 21 | 4 | 100% | 28 | 0 |
| Mar | 34 | 16 | 100% | 29 | 1 |
| Apr | 51 | 29 | 100% | 22 | 24 |
| May | 65 | 42 | 84% | 4 | 178 |
| Jun | 74 | 53 | 0% | 0 | 411 |
| Jul | 79 | 57 | 0% | 0 | 561 |
| Aug | 79 | 54 | 0% | 0 | 517 |
| Sep | 69 | 44 | 61% | 2 | 234 |
| Oct | 53 | 32 | 100% | 17 | 42 |
| Nov | 36 | 18 | 100% | 29 | 3 |
| Dec | 22 | 6 | 100% | 31 | 0 |
Monthly normals 1991–2020 at Carrington, ND (1,586 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
When it snows in Carrington, North Dakota
The first measurable snow (0.1 inch or more) in Carrington usually arrives around November 6, and the last of the season around March 20. Those are the middle dates across the winters of 1991–2020 at Carrington 4 N, ND, 4.4 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 51 days after the last snow.
Planting calendar for 58421
| When | What to do |
|---|---|
| March 1 – March 15 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 15 – March 29 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 12 – April 26 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 10 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 6 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 14 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| September 28 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 58421 is 2 miles from Carrington, ND, which stands at 1,586 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 58421 in zone 4a, the band where the coldest night of the year averaged -30 to -25°F (-34.4 to -31.7°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across North Dakota →
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.