The official National Weather Service forecast for Barnesville — 39.9881°N, 81.1765°W, 5.4 miles from I-70.
| Belmont County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 37 | 41 | 51 | 63 | 73 | 80 | 83 | 82 | 77 | 65 | 52 | 42 | 62 |
| Avg low °F | 21 | 23 | 30 | 39 | 49 | 58 | 62 | 61 | 54 | 43 | 33 | 26 | 42 |
| Precip in | 3.4 | 2.9 | 3.4 | 3.9 | 4.4 | 4.6 | 4.1 | 3.8 | 3.5 | 3.2 | 2.8 | 3.2 | 43.2 |
1996–2025 normals for Belmont County — the climate division Barnesville sits in. All-time county record high 99.0°F (1953-09-03); record low -23.8°F (1994-01-19). Source: NOAA / National Weather Service.