The official National Weather Service forecast for Shelby — 48.5053°N, 111.857°W, 1.2 miles from I-15.
| Toole County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 32 | 33 | 43 | 54 | 64 | 72 | 83 | 81 | 71 | 56 | 42 | 33 | 55 |
| Avg low °F | 10 | 11 | 19 | 28 | 38 | 46 | 51 | 50 | 42 | 30 | 20 | 11 | 30 |
| Precip in | 0.5 | 0.5 | 0.6 | 1.1 | 1.9 | 2.8 | 0.9 | 1.1 | 1.2 | 0.8 | 0.6 | 0.4 | 12.4 |
1996–2025 normals for Toole County — the climate division Shelby sits in. All-time county record high 106.6°F (1961-08-06); record low -46.6°F (1968-12-30). Source: NOAA / National Weather Service.