The official National Weather Service forecast for Mountain Home — 43.133°N, 115.6912°W, population 17,799, 1.4 miles from I-84. Forecasts here are written by NWS BOI, this county’s forecast office.
| Elmore County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 37 | 41 | 49 | 57 | 66 | 76 | 88 | 86 | 76 | 61 | 46 | 36 | 60 |
| Avg low °F | 20 | 22 | 27 | 32 | 40 | 47 | 56 | 53 | 45 | 35 | 27 | 21 | 35 |
| Precip in | 2.9 | 2.2 | 2.1 | 1.6 | 1.6 | 0.9 | 0.3 | 0.3 | 0.6 | 1.4 | 2.0 | 3.4 | 19.3 |
1996–2025 normals for Elmore County — the climate division Mountain Home sits in. All-time county record high 104.3°F (2002-07-13); record low -24.1°F (1990-12-23). Source: NOAA / National Weather Service.