The official National Weather Service forecast for Callaway — 41.2919°N, 99.9226°W, 28.8 miles from I-80.
| Custer County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 37 | 40 | 52 | 62 | 71 | 82 | 87 | 85 | 79 | 64 | 51 | 40 | 62 |
| Avg low °F | 14 | 16 | 26 | 34 | 45 | 56 | 61 | 60 | 50 | 37 | 25 | 16 | 37 |
| Precip in | 0.4 | 0.6 | 1.3 | 2.5 | 4.1 | 3.7 | 3.1 | 2.8 | 2.0 | 1.9 | 0.8 | 0.6 | 23.8 |
1996–2025 normals for Custer County — the climate division Callaway sits in. All-time county record high 108.4°F (1954-07-11); record low -29.0°F (1983-12-22). Source: NOAA / National Weather Service.