The official National Weather Service forecast for Lima — 44.6369°N, 112.5919°W, 0.5 miles from I-15.
| Beaverhead County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 29 | 30 | 39 | 47 | 56 | 65 | 77 | 74 | 64 | 50 | 37 | 28 | 50 |
| Avg low °F | 12 | 12 | 19 | 24 | 32 | 39 | 46 | 45 | 38 | 29 | 19 | 12 | 27 |
| Precip in | 1.5 | 1.5 | 1.6 | 2.0 | 2.6 | 2.3 | 0.9 | 1.2 | 1.4 | 1.6 | 1.4 | 1.7 | 19.7 |
1996–2025 normals for Beaverhead County — the climate division Lima sits in. All-time county record high 92.3°F (2002-07-13); record low -35.7°F (1979-01-01). Source: NOAA / National Weather Service.