Frost dates / South Dakota / Sioux Falls
Frost dates in Sioux Falls, SD
The station on this page is SIOUX FALLS, SD US (USW00014944), 3.3 miles from the city point. Population in the Census 2024 estimate is 209,289.
Zone 5aUSDA average annual extreme minimum -20°F to -15°F, from ZIP 57117 (1.3 miles from the city point used on this page).
Outside the median season Growing seasonTicks: 10%, 50%, and 90%
Last 32°F in spring
NCEI’s probability is the chance the last spring minimum of 32°F or lower occurs on or after the date.
| Probability | Date | How to read it |
|---|---|---|
| 90% | April 18 | Earlier date. A last 32°F on or after this day is common. |
| 50% | May 1 | Median. |
| 10% | May 14 | Later date. A last 32°F on or after this day is uncommon. |
First 32°F in fall
NCEI’s probability is the chance the first autumn minimum of 32°F or lower occurs on or before the date.
| Probability | Date | How to read it |
|---|---|---|
| 10% | September 23 | Earlier date. A first 32°F on or before this day is uncommon. |
| 50% | October 6 | Median. |
| 90% | October 20 | Later date. A first 32°F on or before this day is common. |
32°F growing-season length
Days between the last spring 32°F and the first autumn 32°F. The figure is a length the season meets or exceeds at that probability, from NCEI, not a subtraction done on this site.
| Probability the season is at least this long | Days |
|---|---|
| 10% | 176 |
| 50% | 157 |
| 90% | 138 |
28°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 5 | April 22 | April 8 |
| First, on or before | October 1 | October 17 | October 30 |
| Season at least | 196 days | 176 days | 154 days |
36°F threshold
| 10% | 50% | 90% | |
|---|---|---|---|
| Last, on or after | May 23 | May 10 | April 29 |
| First, on or before | September 14 | September 27 | October 10 |
| Season at least | 156 days | 139 days | 121 days |
Station SIOUX FALLS, SD US (USW00014944). Completeness flag S, 29 years used for the 32°F dates. NCEI’s annual probability of at least one day at or below 32°F is 100%. Freeze dates are conditional on that threshold occurring. Elevation 435.9 m. The same probability language applies to the 28°F and 36°F rows when those dates passed the same quality checks.
Check a crop against this station
Sioux Falls, SD
Zone 5aAverage annual extreme minimum -20°F to -15°F
Outside the median season Growing seasonTicks: 10%, 50%, and 90%
South Dakota. Nearest qualified station: SIOUX FALLS, SD US (USW00014944), 3.3 miles. Median last 32°F May 1. Median first 32°F October 6. The 50% growing-season length is 157 days.
32°F probabilities at this station
| 10% | 50% | 90% | |
|---|---|---|---|
| Last 32°F on or after | May 14 | May 1 | April 18 |
| First 32°F on or before | September 23 | October 6 | October 20 |
Column order matches the NCEI file: for the last freeze, 10% is the later date and 90% is the earlier date. How to read the probabilities.
Planting calendar
Frost dates for South Dakota are above. Planting windows appear for states with a cited extension guide. The fall and seed tools use the numbers you enter and the station dates.
Date checks use your device’s calendar and appear after the page loads.