The official National Weather Service forecast for Garretson — 43.7175°N, 96.5028°W, 7.9 miles from I-90.
| Minnehaha County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 26 | 31 | 43 | 58 | 70 | 80 | 84 | 81 | 75 | 61 | 45 | 30 | 57 |
| Avg low °F | 8 | 11 | 23 | 34 | 46 | 58 | 62 | 59 | 51 | 38 | 24 | 13 | 36 |
| Precip in | 0.6 | 0.7 | 1.4 | 2.7 | 3.6 | 4.3 | 3.0 | 3.3 | 2.7 | 2.2 | 1.1 | 0.9 | 26.5 |
1996–2025 normals for Minnehaha County — the climate division Garretson sits in. All-time county record high 105.9°F (1988-06-22); record low -34.3°F (1970-01-19). Source: NOAA / National Weather Service.