The official National Weather Service forecast for Libby — 48.3883°N, 115.556°W, population 4,341, 63.5 miles from I-90.
| Lincoln County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 31 | 34 | 43 | 51 | 61 | 68 | 79 | 78 | 67 | 51 | 37 | 30 | 52 |
| Avg low °F | 19 | 18 | 24 | 29 | 37 | 43 | 49 | 48 | 41 | 32 | 25 | 19 | 32 |
| Precip in | 3.4 | 2.7 | 3.2 | 2.3 | 2.8 | 2.7 | 1.0 | 1.2 | 1.7 | 2.9 | 4.1 | 4.0 | 32.0 |
1996–2025 normals for Lincoln County — the climate division Libby sits in. All-time county record high 98.7°F (2018-08-11); record low -35.8°F (1968-12-30). Source: NOAA / National Weather Service.