South Dakota frost dates
The typical last spring frost ranges from May 1 in Sioux Falls to May 28 in Keystone.
4 of the 4 South Dakota cities listed have typical frost dates. The longest frost-free season is 157 days in Rapid City; the shortest is 112 days in Keystone. For a single address, look up your ZIP code: rural ZIPs use their nearest suitable station.
| City | Last spring frost | 1 in 10 after | First fall frost | 1 in 10 before | Hard freeze (28°F) | Season |
|---|---|---|---|---|---|---|
| Aberdeen | May 9 | May 22 | Sep 26 | Sep 14 | Apr 30 / Oct 4 | 139 days |
| Keystone | May 28 | Jun 11 | Sep 18 | Sep 4 | May 15 / Sep 29 | 112 days |
| Rapid City | May 3 | May 17 | Oct 8 | Sep 26 | Apr 22 / Oct 18 | 157 days |
| Sioux Falls | May 1 | May 14 | Oct 6 | Sep 23 | Apr 22 / Oct 17 | 157 days |
Reading the table: Aberdeen
In Aberdeen, the last spring frost typically comes around May 9: in half of years it is earlier, in half later. In 1 year in 10 it comes after May 22, 13 days later, so tender plants set out after that date have a 90% chance of escaping frost. In fall, the first frost typically arrives around Sep 26, and in 1 year in 10 before Sep 14. Hard freezes (28°F) usually end earlier in spring and start later in fall: around Apr 30 and Oct 4 in Aberdeen.
Frost dates at more South Dakota weather stations
NOAA stations across South Dakota used by our ZIP code lookup, named for the town they are in.
| Station | Elevation | Last spring frost | First fall frost |
|---|---|---|---|
| Alexandria | 1,365 ft | May 8 (1 in 10 after May 21) | Sep 29 (before Sep 17) |
| Arlington 1 W | 1,824 ft | May 3 (1 in 10 after May 15) | Oct 2 (before Sep 19) |
| Armour | 1,510 ft | May 3 (1 in 10 after May 18) | Oct 6 (before Sep 23) |
| Astoria 4S | 1,890 ft | May 6 (1 in 10 after May 20) | Oct 3 (before Sep 20) |
| Bison | 2,780 ft | May 10 (1 in 10 after May 24) | Oct 1 (before Sep 16) |
| Bonesteel | 1,985 ft | May 3 (1 in 10 after May 15) | Oct 10 (before Sep 26) |
| Bridgewater | 1,417 ft | Apr 30 (1 in 10 after May 11) | Oct 7 (before Sep 25) |
| Britton | 1,355 ft | May 13 (1 in 10 after May 27) | Sep 26 (before Sep 14) |
| Brookings 2 Ne | 1,639 ft | May 6 (1 in 10 after May 19) | Oct 1 (before Sep 17) |
| Camp Crook | 3,120 ft | May 17 (1 in 10 after May 30) | Sep 24 (before Sep 9) |
| Canton | 1,316 ft | May 2 (1 in 10 after May 15) | Oct 2 (before Sep 19) |
| Castlewood | 1,685 ft | May 10 (1 in 10 after May 23) | Sep 27 (before Sep 14) |
| Cedar Butte | 2,355 ft | May 6 (1 in 10 after May 22) | Oct 4 (before Sep 22) |
| Centerville 6 Se | 1,276 ft | May 2 (1 in 10 after May 15) | Oct 1 (before Sep 17) |
| Chamberlain 5 S | 1,704 ft | May 3 (1 in 10 after May 17) | Oct 7 (before Sep 25) |
| Clark | 1,804 ft | May 5 (1 in 10 after May 18) | Oct 5 (before Sep 24) |
| Clear Lake | 1,812 ft | May 7 (1 in 10 after May 21) | Oct 1 (before Sep 19) |
| Columbia 8 N | 1,305 ft | May 7 (1 in 10 after May 22) | Sep 29 (before Sep 18) |
| De Smet | 1,705 ft | May 5 (1 in 10 after May 20) | Oct 4 (before Sep 23) |
| Elm Springs 3 Ese | 2,645 ft | May 8 (1 in 10 after May 22) | Oct 3 (before Sep 18) |
| Faulkton 1 Nw | 1,597 ft | May 10 (1 in 10 after May 25) | Sep 28 (before Sep 15) |
| Flandreau | 1,567 ft | May 5 (1 in 10 after May 17) | Oct 1 (before Sep 19) |
| Gettysburg | 2,084 ft | May 7 (1 in 10 after May 21) | Oct 2 (before Sep 21) |
| Gregory | 2,160 ft | May 6 (1 in 10 after May 20) | Oct 3 (before Sep 21) |
| Harrington | 2,980 ft | May 11 (1 in 10 after May 24) | Oct 1 (before Sep 18) |
| Highmore 1 W | 1,888 ft | May 12 (1 in 10 after May 28) | Oct 1 (before Sep 17) |
| Howard | 1,570 ft | May 5 (1 in 10 after May 18) | Oct 2 (before Sep 19) |
| Huron Rgnl Airport | 1,280 ft | May 6 (1 in 10 after May 20) | Oct 2 (before Sep 19) |
| Lead | 5,112 ft | May 18 (1 in 10 after Jun 1) | Sep 29 (before Sep 15) |
| Madison 2SE | 1,643 ft | May 5 (1 in 10 after May 18) | Sep 30 (before Sep 18) |
| Mc Intosh 6 Se | 2,179 ft | May 9 (1 in 10 after May 24) | Sep 30 (before Sep 19) |
| Mc Laughlin | 2,001 ft | May 12 (1 in 10 after May 25) | Sep 28 (before Sep 16) |
| Mellette 4 W | 1,296 ft | May 11 (1 in 10 after May 23) | Sep 27 (before Sep 15) |
| Menno | 1,332 ft | May 1 (1 in 10 after May 14) | Oct 4 (before Sep 21) |
| Miller | 1,576 ft | May 3 (1 in 10 after May 16) | Oct 3 (before Sep 20) |
| Mitchell Muni Airport | 1,303 ft | Apr 30 (1 in 10 after May 13) | Oct 5 (before Sep 22) |
| Mobridge Muni Airport | 1,715 ft | May 5 (1 in 10 after May 20) | Oct 4 (before Sep 21) |
| Newell | 2,860 ft | May 8 (1 in 10 after May 22) | Oct 1 (before Sep 19) |
| Pickstown | 1,490 ft | Apr 30 (1 in 10 after May 12) | Oct 13 (before Sep 29) |
| Pierre Rgnl Airport | 1,742 ft | May 6 (1 in 10 after May 21) | Oct 3 (before Sep 20) |
| Pine Ridge Airport | 3,278 ft | May 16 (1 in 10 after May 31) | Sep 27 (before Sep 13) |
| Pollock | 1,639 ft | May 8 (1 in 10 after May 21) | Sep 30 (before Sep 18) |
| Rapid City Rgnl Airport | 3,160 ft | May 12 (1 in 10 after May 26) | Oct 1 (before Sep 16) |
| Red Owl | 2,773 ft | May 16 (1 in 10 after May 27) | Sep 26 (before Sep 11) |
| Redfield | 1,309 ft | May 8 (1 in 10 after May 21) | Oct 1 (before Sep 19) |
| Roscoe | 1,835 ft | May 7 (1 in 10 after May 20) | Oct 3 (before Sep 19) |
| Selby | 1,908 ft | May 8 (1 in 10 after May 21) | Oct 1 (before Sep 19) |
| Sisseton | 1,209 ft | May 4 (1 in 10 after May 17) | Oct 3 (before Sep 22) |
| Summit 1 W | 1,955 ft | May 14 (1 in 10 after May 28) | Sep 28 (before Sep 13) |
| Timber Lake | 2,173 ft | May 10 (1 in 10 after May 23) | Sep 30 (before Sep 17) |
| Tyndall | 1,420 ft | May 1 (1 in 10 after May 14) | Oct 7 (before Sep 24) |
| Vermillion 2 Se | 1,137 ft | May 3 (1 in 10 after May 16) | Oct 3 (before Sep 20) |
| Victor 4 N | 1,095 ft | May 4 (1 in 10 after May 17) | Oct 3 (before Sep 21) |
| Watertown Rgnl Airport | 1,748 ft | May 7 (1 in 10 after May 20) | Sep 30 (before Sep 19) |
| Waubay Natl Wild Life | 1,827 ft | May 1 (1 in 10 after May 12) | Oct 12 (before Sep 30) |
| Webster | 1,861 ft | May 4 (1 in 10 after May 16) | Oct 6 (before Sep 25) |
| White Lake | 1,629 ft | May 3 (1 in 10 after May 17) | Oct 5 (before Sep 21) |
| Winner Wiley Fld | 2,032 ft | May 1 (1 in 10 after May 15) | Oct 10 (before Sep 27) |
| Wood | 2,180 ft | May 10 (1 in 10 after May 22) | Oct 1 (before Sep 19) |
| Yankton 2 E | 1,180 ft | Apr 27 (1 in 10 after May 10) | Oct 11 (before Sep 27) |
32°F dates from NOAA 1991-2020 freeze probabilities for each city's station. "1 in 10 after": a 10% chance of a later spring frost (planting is 90% safe after it). How to read frost dates.