The official National Weather Service forecast for Garden Valley — 44.0899°N, 115.9521°W, 38 miles from I-84. Forecasts here are written by NWS BOI, this county’s forecast office.
| Boise County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 34 | 38 | 46 | 52 | 62 | 71 | 83 | 81 | 72 | 57 | 42 | 33 | 56 |
| Avg low °F | 18 | 18 | 24 | 29 | 36 | 43 | 51 | 50 | 42 | 33 | 25 | 18 | 32 |
| Precip in | 4.4 | 3.5 | 3.5 | 2.5 | 2.3 | 1.5 | 0.4 | 0.5 | 1.0 | 2.2 | 3.3 | 5.3 | 30.4 |
1996–2025 normals for Boise County — the climate division Garden Valley sits in. All-time county record high 100.3°F (2002-07-13); record low -26.6°F (1962-01-22). Source: NOAA / National Weather Service.