The official National Weather Service forecast for Salem — 43.7242°N, 97.3889°W, 11.6 miles from I-90.
| McCook County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 26 | 31 | 44 | 58 | 70 | 80 | 85 | 82 | 76 | 61 | 45 | 30 | 57 |
| Avg low °F | 8 | 11 | 23 | 34 | 46 | 58 | 62 | 59 | 51 | 37 | 24 | 13 | 36 |
| Precip in | 0.6 | 0.8 | 1.3 | 2.7 | 3.6 | 4.0 | 2.9 | 3.2 | 2.7 | 2.1 | 1.0 | 0.9 | 25.8 |
1996–2025 normals for McCook County — the climate division Salem sits in. All-time county record high 105.4°F (1988-06-22); record low -34.8°F (1970-01-19). Source: NOAA / National Weather Service.