USDA Hardiness Zone 3b
Frost Dates for 55769 — Nashwauk, Minnesota
NOAA 1991–2020 normals from Hibbing Chisholm Hibbing Airport, MN (1,352 ft), 15 miles east.
Updated
In Nashwauk, the last spring frost (32°F) is around June 5 in half of years and has passed by June 25 in nine years out of ten. The first fall frost comes around September 8, as early as August 23 one year in ten, leaving a typical freeze-free season of 93 days (NOAA, Hibbing Chisholm Hibbing Airport, MN).
- Last spring frost
- June 5
- First fall frost
- September 8
- Growing season
- 93 days
- Hardiness zone
- 3b
50% probability
50% probability
freeze-free, 50%
-35 to -30°F (-37.2 to -34.4°C) coldest night
- First snow
- October 29
- Last snow
- April 24
- Winters with snow
- 100%
- Snow per year
- 59.6"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Nashwauk
Half of springs at Hibbing Chisholm Hibbing Airport, MN see their last 32°F night by June 5; only one in ten is past it by May 22, and one in ten still has one after June 25. Planting tender crops after June 12 leaves a 30% risk of a frost on them, after June 17 20%, and after June 25 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 99% of the 142 Minnesota stations behind this site's ZIP pages.
In fall the first 32°F night comes by September 8 in half of years, as early as August 23 one year in ten, and holds off past September 23 one year in ten. A hard freeze of 28°F follows 13 days later, around September 21; in spring the one-in-ten date for 28°F is June 7, 18 days before the 32°F one. The freeze-free season lasts 93 days in a typical year, the shortest of the 142 Minnesota stations; it reaches 115 days one year in ten and falls short of 67 one year in ten. On average 205 nights a year drop to 32°F or below. Severe cold of 16°F or below comes every winter, usually between October 31 and April 16.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | too rare for a date | ||||||||
| 32°F | May 22 | May 27 | May 30 | Jun 2 | Jun 5 | Jun 8 | Jun 12 | Jun 17 | Jun 25 |
| 28°F | May 6 | May 12 | May 16 | May 20 | May 23 | May 26 | May 29 | Jun 1 | Jun 7 |
| 24°F | Apr 25 | Apr 29 | May 1 | May 4 | May 7 | May 11 | May 15 | May 19 | May 24 |
| 20°F | Apr 12 | Apr 18 | Apr 21 | Apr 25 | Apr 28 | Apr 30 | May 3 | May 7 | May 12 |
| 16°F | Apr 2 | Apr 6 | Apr 9 | Apr 13 | Apr 16 | Apr 19 | Apr 22 | Apr 26 | Apr 30 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | too rare for a date | ||||||||
| 32°F | Aug 23 | Aug 29 | Sep 2 | Sep 5 | Sep 8 | Sep 12 | Sep 15 | Sep 19 | Sep 23 |
| 28°F | Sep 4 | Sep 11 | Sep 15 | Sep 18 | Sep 21 | Sep 24 | Sep 27 | Oct 1 | Oct 5 |
| 24°F | Sep 16 | Sep 21 | Sep 25 | Sep 29 | Oct 1 | Oct 3 | Oct 6 | Oct 11 | Oct 17 |
| 20°F | Sep 28 | Oct 3 | Oct 7 | Oct 11 | Oct 15 | Oct 19 | Oct 22 | Oct 27 | Nov 1 |
| 16°F | Oct 12 | Oct 18 | Oct 22 | Oct 27 | Oct 31 | Nov 2 | Nov 4 | Nov 7 | Nov 12 |
Freeze probabilities 1991–2020 at Hibbing Chisholm Hibbing Airport, MN, 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 55769 →Compare Nashwauk with another place →
Weather by month in Nashwauk
July is the warmest month at Hibbing Chisholm Hibbing Airport, MN, averaging 77°F by day and 50°F at night; January is the coldest at 17°F and -4°F. A freezing night is all but certain in every month from September to May (a 90% chance or more). July is the only month with under a 10% chance of a 32°F night. In spring, June still brings one in 62% of years.
Warmth for growing adds up to 1,336 growing degree days a year (base 50°F), fewer than at 99% of the 142 Minnesota stations. 29% of them (384) have built up by the end of June, and July adds the most, 419. Precipitation totals 24.9 inches a year, most in June (4.4") and least in January (0.5"); May to September bring 69% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 17 | -4 | 0.5 | 100% | 31 | 0 |
| Feb | 23 | -1 | 0.5 | 100% | 28 | 0 |
| Mar | 35 | 12 | 0.9 | 100% | 29 | 1 |
| Apr | 50 | 25 | 1.6 | 100% | 24 | 10 |
| May | 63 | 36 | 2.8 | 100% | 10 | 97 |
| Jun | 72 | 46 | 4.4 | 62% | 1 | 276 |
| Jul | 77 | 50 | 3.9 | 8% | 0 | 419 |
| Aug | 75 | 48 | 3.1 | 25% | <1 | 361 |
| Sep | 66 | 40 | 3.1 | 98% | 6 | 152 |
| Oct | 51 | 30 | 2.4 | 100% | 19 | 20 |
| Nov | 34 | 17 | 1.1 | 100% | 28 | 1 |
| Dec | 21 | 3 | 0.6 | 100% | 31 | 0 |
Monthly normals 1991–2020 at Hibbing Chisholm Hibbing Airport, MN (1,352 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, Grand Rpds Forest Lab, MN, 19 miles southwest of Nashwauk, has a last frost 19 days earlier (May 17), a first frost 16 days later (September 24), a season 37 days longer.
When it snows in Nashwauk, Minnesota
The first measurable snow (0.1 inch or more) in Nashwauk usually arrives around October 29, and the last of the season around April 24. Those are the middle dates across the winters of 1991–2020 at Grand Rpds Forest Lab, MN, 19.2 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 42 days after the last snow.
Planting calendar for 55769
| When | What to do |
|---|---|
| March 27 – April 10 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| April 10 – April 24 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| May 8 – May 22 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| June 5 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by June 16 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by August 25 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| September 8 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 55769 is 15 miles from Hibbing Chisholm Hibbing Airport, MN, which stands at 1,352 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 55746 (Hibbing). The 2023 USDA Plant Hardiness Zone Map lists ZIP 55769 in zone 3b, the band where the coldest night of the year averaged -35 to -30°F (-37.2 to -34.4°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Minnesota →
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.