The official National Weather Service forecast for Manhattan — 39.1836°N, 96.5717°W, population 60,454, 8.9 miles from I-70.
| Riley County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 39 | 44 | 56 | 67 | 76 | 86 | 90 | 88 | 82 | 69 | 55 | 43 | 66 |
| Avg low °F | 18 | 21 | 32 | 42 | 53 | 63 | 68 | 66 | 57 | 44 | 32 | 22 | 43 |
| Precip in | 0.8 | 1.1 | 1.8 | 3.2 | 4.9 | 4.7 | 3.9 | 4.0 | 2.8 | 2.5 | 1.6 | 1.1 | 32.4 |
1996–2025 normals for Riley County — the climate division Manhattan sits in. All-time county record high 110.4°F (1954-07-13); record low -23.5°F (1989-12-23). Source: NOAA / National Weather Service.