USDA Hardiness Zone 5a
Frost Dates for 57764 — Oglala, South Dakota
NOAA 1991–2020 normals from Oglala 1S, SD (2,995 ft), 6 miles south.
Updated
In Oglala, the last spring frost (32°F) is around May 7 in half of years and has passed by May 21 in nine years out of ten. The first fall frost comes around October 4, as early as September 21 one year in ten, leaving a typical freeze-free season of 149 days (NOAA, Oglala 1S, SD).
- Last spring frost
- May 7
- First fall frost
- October 4
- Growing season
- 149 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 23
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
17 of 17 observed
NOAA normal
Frost risk by date in Oglala
Half of springs at Oglala 1S, SD see their last 32°F night by May 7; only one in ten is past it by April 24, and one in ten still has one after May 21. Planting tender crops after May 13 leaves a 30% risk of a frost on them, after May 16 20%, and after May 21 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 59% of the 49 South Dakota stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 4 in half of years, as early as September 21 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 12 days later, around October 16; in spring the one-in-ten date for 28°F is May 11, 10 days before the 32°F one. The freeze-free season lasts 149 days in a typical year, longer than at 51% of the 49 South Dakota stations; it reaches 167 days one year in ten and falls short of 128 one year in ten. On average 162 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 17, and return around September 26. Severe cold of 16°F or below comes every winter, usually between November 9 and March 26.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 5 | May 8 | May 12 | May 14 | May 17 | May 20 | May 23 | May 25 | May 29 |
| 32°F | Apr 24 | Apr 29 | May 1 | May 4 | May 7 | May 9 | May 13 | May 16 | May 21 |
| 28°F | Apr 12 | Apr 17 | Apr 21 | Apr 24 | Apr 27 | Apr 30 | May 2 | May 5 | May 11 |
| 24°F | Mar 31 | Apr 5 | Apr 9 | Apr 12 | Apr 15 | Apr 19 | Apr 22 | Apr 26 | Apr 30 |
| 20°F | Mar 19 | Mar 25 | Mar 30 | Apr 2 | Apr 5 | Apr 8 | Apr 12 | Apr 16 | Apr 21 |
| 16°F | Mar 6 | Mar 12 | Mar 19 | Mar 22 | Mar 26 | Mar 31 | Apr 3 | Apr 7 | Apr 13 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 12 | Sep 17 | Sep 21 | Sep 24 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 8 |
| 32°F | Sep 21 | Sep 26 | Sep 30 | Oct 2 | Oct 4 | Oct 7 | Oct 10 | Oct 14 | Oct 19 |
| 28°F | Oct 1 | Oct 5 | Oct 9 | Oct 13 | Oct 16 | Oct 18 | Oct 21 | Oct 24 | Oct 28 |
| 24°F | Oct 9 | Oct 15 | Oct 18 | Oct 22 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 6 |
| 20°F | Oct 17 | Oct 22 | Oct 25 | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 10 | Nov 16 |
| 16°F | Oct 24 | Oct 28 | Nov 1 | Nov 5 | Nov 9 | Nov 12 | Nov 16 | Nov 20 | Nov 25 |
Freeze probabilities 1991–2020 at Oglala 1S, 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 57764 →Compare Oglala with another place →
Weather by month in Oglala
July is the warmest month at Oglala 1S, SD, averaging 88°F by day and 61°F at night; January is the coldest at 37°F and 14°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 73% of years.
Warmth for growing adds up to 2,874 growing degree days a year (base 50°F), more than at 73% of the 49 South Dakota stations. 30% of them (862) have built up by the end of June, and July adds the most, 762.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 37 | 14 | 100% | 30 | 0 |
| Feb | 41 | 17 | 100% | 27 | 2 |
| Mar | 51 | 25 | 100% | 25 | 26 |
| Apr | 60 | 34 | 100% | 12 | 74 |
| May | 69 | 44 | 73% | 3 | 245 |
| Jun | 80 | 54 | 0% | 0 | 517 |
| Jul | 88 | 61 | 0% | 0 | 762 |
| Aug | 88 | 58 | 0% | 0 | 714 |
| Sep | 78 | 49 | 32% | 1 | 410 |
| Oct | 63 | 36 | 100% | 11 | 111 |
| Nov | 49 | 25 | 100% | 24 | 13 |
| Dec | 39 | 16 | 100% | 30 | 1 |
Monthly normals 1991–2020 at Oglala 1S, SD (2,995 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, Pine Ridge Airport, SD, 21 miles southeast of Oglala and 283 feet higher, has a last frost 9 days later (May 16), a first frost 7 days earlier (September 27), a season 17 days shorter.
When it snows in Oglala, South Dakota
The first measurable snow (0.1 inch or more) in Oglala usually arrives around November 10, and the last of the season around April 23. Those are the middle dates across the winters of 1991–2020 at Oglala 1S, SD, 5.9 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 14 days after the last snow.
Planting calendar for 57764
| When | What to do |
|---|---|
| February 26 – March 12 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 12 – March 26 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 9 – April 23 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 7 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 12 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 20 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 4 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 57764 is 6 miles from Oglala 1S, SD, which stands at 2,995 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 57764 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.