The official National Weather Service forecast for Hamersville — 38.9179°N, 83.9833°W, 19.9 miles from I-275.
| Brown County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 40 | 44 | 54 | 66 | 75 | 83 | 86 | 85 | 80 | 68 | 55 | 45 | 65 |
| Avg low °F | 22 | 25 | 32 | 41 | 51 | 59 | 63 | 62 | 55 | 44 | 33 | 27 | 43 |
| Precip in | 3.4 | 3.3 | 4.2 | 4.6 | 5.0 | 4.8 | 4.6 | 3.4 | 3.5 | 3.3 | 3.0 | 3.7 | 46.8 |
1996–2025 normals for Brown County — the climate division Hamersville sits in. All-time county record high 103.0°F (2012-07-08); record low -25.6°F (1994-01-19). Source: NOAA / National Weather Service.