USDA Hardiness Zone 5a
Frost Dates for 57380 — Wagner, South Dakota
NOAA 1991–2020 normals from Wagner, SD (1,430 ft), 3 miles north.
Updated
In Wagner, the last spring frost (32°F) is around April 29 in half of years and has passed by May 12 in nine years out of ten. The first fall frost comes around October 9, as early as September 25 one year in ten, leaving a typical freeze-free season of 164 days (NOAA, Wagner, SD).
- Last spring frost
- April 29
- First fall frost
- October 9
- Growing season
- 164 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 10
- Last snow
- April 12
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
21 of 21 observed
NOAA normal
Frost risk by date in Wagner
Half of springs at Wagner, SD see their last 32°F night by April 29; only one in ten is past it by April 12, and one in ten still has one after May 12. Planting tender crops after May 3 leaves a 30% risk of a frost on them, after May 6 20%, and after May 12 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 43% of the 49 South Dakota stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 9 in half of years, as early as September 25 one year in ten, and holds off past October 23 one year in ten. A hard freeze of 28°F follows 10 days later, around October 19; in spring the one-in-ten date for 28°F is May 2, 10 days before the 32°F one. The freeze-free season lasts 164 days in a typical year, longer than at 94% of the 49 South Dakota stations; it reaches 183 days one year in ten and falls short of 144 one year in ten. On average 150 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 8 days longer, to about May 7, and return around October 1. Severe cold of 16°F or below comes every winter, usually between November 14 and March 22.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 25 | Apr 30 | May 2 | May 5 | May 7 | May 10 | May 13 | May 15 | May 21 |
| 32°F | Apr 12 | Apr 18 | Apr 22 | Apr 26 | Apr 29 | May 1 | May 3 | May 6 | May 12 |
| 28°F | Apr 4 | Apr 8 | Apr 12 | Apr 15 | Apr 18 | Apr 21 | Apr 25 | Apr 28 | May 2 |
| 24°F | Mar 24 | Mar 31 | Apr 3 | Apr 6 | Apr 8 | Apr 12 | Apr 15 | Apr 19 | Apr 24 |
| 20°F | Mar 12 | Mar 19 | Mar 24 | Mar 29 | Apr 1 | Apr 3 | Apr 6 | Apr 10 | Apr 16 |
| 16°F | Mar 4 | Mar 10 | Mar 14 | Mar 18 | Mar 22 | Mar 27 | Mar 31 | Apr 3 | Apr 8 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 19 | Sep 23 | Sep 26 | Sep 28 | Oct 1 | Oct 3 | Oct 6 | Oct 9 | Oct 14 |
| 32°F | Sep 25 | Sep 29 | Oct 3 | Oct 6 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 23 |
| 28°F | Oct 3 | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 2 |
| 24°F | Oct 14 | Oct 20 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 4 | Nov 7 | Nov 13 |
| 20°F | Oct 22 | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 21 |
| 16°F | Oct 30 | Nov 4 | Nov 8 | Nov 11 | Nov 14 | Nov 18 | Nov 21 | Nov 25 | Nov 30 |
Freeze probabilities 1991–2020 at Wagner, SD, 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 57380 →Compare Wagner with another place →
Weather by month in Wagner
July is the warmest month at Wagner, SD, averaging 88°F by day and 64°F at night; January is the coldest at 32°F and 13°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 43% of years.
Warmth for growing adds up to 3,301 growing degree days a year (base 50°F), the most of the 49 South Dakota stations. 34% of them (1,109) have built up by the end of June, and July adds the most, 815. Precipitation totals 26.5 inches a year, most in May (3.8") and least in January (0.7"); May to September bring 61% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 32 | 13 | 0.7 | 100% | 30 | 0 |
| Feb | 37 | 16 | 1.0 | 100% | 26 | 2 |
| Mar | 49 | 26 | 1.4 | 100% | 23 | 23 |
| Apr | 62 | 36 | 3.1 | 100% | 11 | 107 |
| May | 73 | 49 | 3.8 | 43% | 1 | 347 |
| Jun | 83 | 59 | 3.8 | 0% | 0 | 630 |
| Jul | 88 | 64 | 2.6 | 0% | 0 | 815 |
| Aug | 86 | 62 | 3.0 | 0% | 0 | 739 |
| Sep | 78 | 53 | 3.0 | 23% | 1 | 471 |
| Oct | 63 | 40 | 2.4 | 98% | 7 | 147 |
| Nov | 48 | 27 | 0.9 | 100% | 22 | 20 |
| Dec | 35 | 17 | 0.8 | 100% | 30 | 0 |
Monthly normals 1991–2020 at Wagner, SD (1,430 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, Pickstown, SD, 12 miles west of Wagner, has a last frost 1 day later (April 30), a first frost 4 days later (October 13), a season 1 day longer.
When it snows in Wagner, South Dakota
The first measurable snow (0.1 inch or more) in Wagner usually arrives around November 10, and the last of the season around April 12. Those are the middle dates across the winters of 1991–2020 at Wagner, SD, 2.7 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 17 days after the last snow.
Planting calendar for 57380
| When | What to do |
|---|---|
| February 18 – March 4 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 4 – March 18 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 1 – April 15 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 29 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 17 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 25 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 9 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 57380 is 3 miles from Wagner, SD, which stands at 1,430 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 57380 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 South 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.