The official National Weather Service forecast for Seneca — 39.8342°N, 96.0642°W, 48.5 miles from I-29.
| Nemaha County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 37 | 42 | 54 | 65 | 75 | 84 | 88 | 86 | 80 | 68 | 54 | 41 | 64 |
| Avg low °F | 16 | 19 | 31 | 40 | 51 | 62 | 66 | 64 | 55 | 43 | 30 | 20 | 41 |
| Precip in | 0.8 | 1.1 | 1.9 | 3.2 | 5.0 | 4.8 | 4.1 | 3.8 | 2.9 | 2.7 | 1.6 | 1.1 | 33.0 |
1996–2025 normals for Nemaha County — the climate division Seneca sits in. All-time county record high 109.6°F (1980-07-15); record low -25.0°F (1989-12-23). Source: NOAA / National Weather Service.