USDA Hardiness Zone 5a
Frost Dates for 53821 — Prairie Du Chien, Wisconsin
NOAA 1991–2020 normals from Prairie Du Chien, WI (658 ft), 1 miles northwest.
Updated
In Prairie Du Chien, the last spring frost (32°F) is around April 28 in half of years and has passed by May 11 in nine years out of ten. The first fall frost comes around October 12, as early as September 27 one year in ten, leaving a typical freeze-free season of 166 days (NOAA, Prairie Du Chien, WI).
- Last spring frost
- April 28
- First fall frost
- October 12
- Growing season
- 166 days
- Hardiness zone
- 5a
50% probability
50% probability
freeze-free, 50%
-20 to -15°F (-28.9 to -26.1°C) coldest night
- First snow
- November 27
- Last snow
- March 20
- Winters with snow
- 100%
- Snow per year
- 33.8"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Prairie Du Chien
Half of springs at Prairie Du Chien, WI see their last 32°F night by April 28; only one in ten is past it by April 14, and one in ten still has one after May 11. Planting tender crops after May 3 leaves a 30% risk of a frost on them, after May 6 20%, and after May 11 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 84% of the 182 Wisconsin stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 12 in half of years, as early as September 27 one year in ten, and holds off past October 25 one year in ten. A hard freeze of 28°F follows 10 days later, around October 22; in spring the one-in-ten date for 28°F is May 2, 9 days before the 32°F one. The freeze-free season lasts 166 days in a typical year, longer than at 76% of the 182 Wisconsin stations; it reaches 185 days one year in ten and falls short of 146 one year in ten. On average 148 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 9 days longer, to about May 7, and return around October 2. Severe cold of 16°F or below comes every winter, usually between November 22 and March 17.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 22 | Apr 29 | May 1 | May 5 | May 7 | May 10 | May 13 | May 17 | May 21 |
| 32°F | Apr 14 | Apr 18 | Apr 22 | Apr 25 | Apr 28 | Apr 30 | May 3 | May 6 | May 11 |
| 28°F | Apr 2 | Apr 6 | Apr 10 | Apr 13 | Apr 16 | Apr 19 | Apr 23 | Apr 27 | May 2 |
| 24°F | Mar 21 | Mar 27 | Mar 31 | Apr 2 | Apr 4 | Apr 7 | Apr 10 | Apr 15 | Apr 21 |
| 20°F | Mar 10 | Mar 15 | Mar 19 | Mar 23 | Mar 27 | Mar 30 | Apr 1 | Apr 4 | Apr 10 |
| 16°F | Mar 3 | Mar 7 | Mar 11 | Mar 14 | Mar 17 | Mar 20 | Mar 23 | Mar 27 | Mar 31 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 19 | Sep 24 | Sep 27 | Sep 30 | Oct 2 | Oct 5 | Oct 7 | Oct 11 | Oct 15 |
| 32°F | Sep 27 | Oct 2 | Oct 6 | Oct 9 | Oct 12 | Oct 14 | Oct 17 | Oct 20 | Oct 25 |
| 28°F | Oct 7 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 4 |
| 24°F | Oct 20 | Oct 24 | Oct 28 | Oct 30 | Nov 1 | Nov 3 | Nov 7 | Nov 11 | Nov 16 |
| 20°F | Oct 31 | Nov 2 | Nov 5 | Nov 9 | Nov 12 | Nov 16 | Nov 19 | Nov 22 | Nov 28 |
| 16°F | Nov 6 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 25 | Nov 28 | Dec 2 | Dec 7 |
Freeze probabilities 1991–2020 at Prairie Du Chien, WI, 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 53821 →Compare Prairie Du Chien with another place →
Weather by month in Prairie Du Chien
July is the warmest month at Prairie Du Chien, WI, averaging 83°F by day and 63°F at night; January is the coldest at 27°F and 10°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 40% of years.
Warmth for growing adds up to 2,900 growing degree days a year (base 50°F), more than at 96% of the 182 Wisconsin stations. 34% of them (979) have built up by the end of June, and July adds the most, 716. Precipitation totals 37.8 inches a year, most in June (5.8") and least in January (1.2"); May to September bring 60% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 27 | 10 | 1.2 | 100% | 30 | 0 |
| Feb | 32 | 13 | 1.3 | 100% | 26 | 0 |
| Mar | 45 | 25 | 2.1 | 100% | 24 | 17 |
| Apr | 59 | 37 | 4.0 | 100% | 10 | 82 |
| May | 70 | 48 | 4.7 | 40% | 1 | 303 |
| Jun | 80 | 59 | 5.8 | 0% | 0 | 577 |
| Jul | 83 | 63 | 4.1 | 0% | 0 | 716 |
| Aug | 81 | 61 | 4.2 | 0% | 0 | 656 |
| Sep | 74 | 52 | 4.0 | 16% | <1 | 399 |
| Oct | 62 | 40 | 2.7 | 96% | 7 | 133 |
| Nov | 46 | 28 | 2.1 | 100% | 20 | 17 |
| Dec | 33 | 17 | 1.6 | 100% | 29 | 1 |
Monthly normals 1991–2020 at Prairie Du Chien, WI (658 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, Guttenberg L&D 10, IA, 17 miles south of Prairie Du Chien, has a last frost 7 days earlier (April 21), a first frost 6 days later (October 18), a season 12 days longer.
When it snows in Prairie Du Chien, Wisconsin
The first measurable snow (0.1 inch or more) in Prairie Du Chien usually arrives around November 27, and the last of the season around March 20. Those are the middle dates across the winters of 1991–2020 at Prairie Du Chien, WI, 1.3 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 39 days after the last snow.
Planting calendar for 53821
| When | What to do |
|---|---|
| February 17 – March 3 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 3 – March 17 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 31 – April 14 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 28 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 28 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 12 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 53821 is 1 mile from Prairie Du Chien, WI, which stands at 658 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 53821 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Wisconsin →
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.