USDA Hardiness Zone 4b
Frost Dates for 55066 — Red Wing, Minnesota
NOAA 1991–2020 normals from Red Wing Dam 3, MN (677 ft), 6 miles northwest.
Updated
In Red Wing, the last spring frost (32°F) is around April 23 in half of years and has passed by May 7 in nine years out of ten. The first fall frost comes around October 14, as early as September 28 one year in ten, leaving a typical freeze-free season of 173 days (NOAA, Red Wing Dam 3, MN).
- Last spring frost
- April 23
- First fall frost
- October 14
- Growing season
- 173 days
- Hardiness zone
- 4b
50% probability
50% probability
freeze-free, 50%
-25 to -20°F (-31.7 to -28.9°C) coldest night
- First snow
- November 21
- Last snow
- March 29
- Winters with snow
- 100%
- Snow per year
- 44.1"
median, 1991–2020
median, 1991–2020
29 of 29 observed
NOAA normal
Frost risk by date in Red Wing
Half of springs at Red Wing Dam 3, MN see their last 32°F night by April 23; only one in ten is past it by April 8, and one in ten still has one after May 7. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 2 20%, and after May 7 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 37% of the 142 Minnesota stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 14 in half of years, as early as September 28 one year in ten, and holds off past October 28 one year in ten. A hard freeze of 28°F follows 11 days later, around October 25; in spring the one-in-ten date for 28°F is April 28, 9 days before the 32°F one. The freeze-free season lasts 173 days in a typical year, longer than at 94% of the 142 Minnesota stations; it reaches 192 days one year in ten and falls short of 152 one year in ten. On average 154 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 May 4, and return around October 4. Severe cold of 16°F or below comes every winter, usually between November 20 and March 22.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 21 | Apr 26 | Apr 30 | May 2 | May 4 | May 7 | May 9 | May 13 | May 19 |
| 32°F | Apr 8 | Apr 14 | Apr 17 | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 2 | May 7 |
| 28°F | Apr 1 | Apr 4 | Apr 7 | Apr 9 | Apr 12 | Apr 16 | Apr 19 | Apr 23 | Apr 28 |
| 24°F | Mar 21 | Mar 27 | Mar 31 | Apr 2 | Apr 4 | Apr 6 | Apr 9 | Apr 12 | Apr 18 |
| 20°F | Mar 14 | Mar 19 | Mar 22 | Mar 25 | Mar 29 | Mar 31 | Apr 2 | Apr 5 | Apr 9 |
| 16°F | Mar 8 | Mar 12 | Mar 16 | Mar 19 | Mar 22 | Mar 24 | Mar 28 | Mar 31 | Apr 3 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 20 | Sep 25 | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 13 | Oct 18 |
| 32°F | Sep 28 | Oct 3 | Oct 7 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 28 |
| 28°F | Oct 10 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 7 |
| 24°F | Oct 20 | Oct 26 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 17 |
| 20°F | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 26 |
| 16°F | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 20 | Nov 23 | Nov 26 | Nov 29 | Dec 4 |
Freeze probabilities 1991–2020 at Red Wing Dam 3, 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 55066 →Compare Red Wing with another place →
Frost risk through the year in Red Wing
In Red Wing, the spring curve drops under 10% on May 7 and the fall curve passes 10% on September 28, 144 days later; that gap is longer than at 91% of the 142 Minnesota stations with frost dates. The spring risk falls from 90% to 10% over 29 days (April 8 to May 7) and the fall risk climbs from 10% to 90% over 30 days (September 28 to October 28): both ends of the season vary about as much. At Ellsworth 1E, WI, 14 miles north, the same gap runs from May 27 to September 15, 33 days shorter.
| Planted on | Another 32°F night | 28°F night |
|---|---|---|
| Apr 9 | 88% | 60% |
| Apr 16 | 73% | 40% |
| Apr 2350% date | 50% | 20% |
| Apr 30 | 30% | under 10% |
| May 7 | under 10% | under 10% |
| May 14 | under 10% | under 10% |
Weather by month in Red Wing
July is the warmest month at Red Wing Dam 3, MN, averaging 82°F by day and 62°F at night; January is the coldest at 23°F and 6°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 24% of years.
Warmth for growing adds up to 2,702 growing degree days a year (base 50°F), more than at 82% of the 142 Minnesota stations. 33% of them (893) have built up by the end of June, and July adds the most, 694. Precipitation totals 32.6 inches a year, most in June (5.1") and least in January (0.8"); May to September bring 65% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 23 | 6 | 0.8 | 100% | 31 | 0 |
| Feb | 28 | 9 | 0.9 | 100% | 27 | 0 |
| Mar | 41 | 22 | 1.7 | 100% | 25 | 9 |
| Apr | 56 | 36 | 2.9 | 98% | 10 | 62 |
| May | 68 | 48 | 4.1 | 24% | 1 | 275 |
| Jun | 78 | 58 | 5.1 | 0% | 0 | 546 |
| Jul | 82 | 62 | 3.8 | 0% | 0 | 694 |
| Aug | 80 | 60 | 4.5 | 0% | 0 | 625 |
| Sep | 73 | 52 | 3.7 | 13% | <1 | 378 |
| Oct | 59 | 39 | 2.5 | 94% | 7 | 103 |
| Nov | 42 | 26 | 1.6 | 100% | 23 | 10 |
| Dec | 29 | 14 | 1.0 | 100% | 30 | 0 |
Monthly normals 1991–2020 at Red Wing Dam 3, MN (677 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, Ellsworth 1E, WI, 14 miles north of Red Wing and 353 feet higher, has a last frost 20 days later (May 13), a first frost 15 days earlier (September 29), a season 34 days shorter.
When it snows in Red Wing, Minnesota
The first measurable snow (0.1 inch or more) in Red Wing usually arrives around November 21, and the last of the season around March 29. Those are the middle dates across the winters of 1991–2020 at Red Wing, MN, 2.3 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 25 days after the last snow.
Planting calendar for 55066
| When | What to do |
|---|---|
| February 12 – February 26 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 26 – March 12 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 26 – April 9 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 23 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 22 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 30 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 14 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 55066 is 6 miles from Red Wing Dam 3, MN, which stands at 677 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 55066 in zone 4b, the band where the coldest night of the year averaged -25 to -20°F (-31.7 to -28.9°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.