The official National Weather Service forecast for Helena — 33.2962°N, 86.8436°W, 5.2 miles from I-65. Forecasts here are written by NWS BMX, this county’s forecast office.
| Shelby County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 55 | 60 | 68 | 75 | 83 | 88 | 91 | 90 | 86 | 76 | 66 | 58 | 75 |
| Avg low °F | 33 | 37 | 43 | 49 | 58 | 66 | 69 | 69 | 63 | 51 | 41 | 36 | 51 |
| Precip in | 5.5 | 5.5 | 5.8 | 5.0 | 4.6 | 5.1 | 5.1 | 4.2 | 3.7 | 3.1 | 4.1 | 5.0 | 56.7 |
1996–2025 normals for Shelby County — the climate division Helena sits in. All-time county record high 105.3°F (1952-07-29); record low -4.7°F (1985-01-21). Source: NOAA / National Weather Service.