The official National Weather Service forecast for Rockingham — 43.1876°N, 72.489°W, 3.6 miles from I-91.
| Windham County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 30 | 33 | 41 | 54 | 66 | 74 | 79 | 78 | 71 | 58 | 46 | 35 | 55 |
| Avg low °F | 12 | 13 | 21 | 31 | 42 | 51 | 56 | 55 | 47 | 37 | 27 | 18 | 34 |
| Precip in | 3.7 | 3.3 | 3.9 | 4.4 | 4.4 | 4.9 | 4.7 | 4.3 | 4.3 | 5.1 | 3.7 | 4.8 | 51.5 |
1996–2025 normals for Windham County — the climate division Rockingham sits in. All-time county record high 94.2°F (1953-07-19); record low -27.1°F (1957-01-14). Source: NOAA / National Weather Service.