The official National Weather Service forecast for New Plymouth — 43.9699°N, 116.819°W, 4.1 miles from I-84. Forecasts here are written by NWS BOI, this county’s forecast office.
| Payette County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 38 | 44 | 56 | 63 | 73 | 82 | 93 | 91 | 80 | 65 | 49 | 38 | 64 |
| Avg low °F | 24 | 27 | 33 | 37 | 45 | 52 | 60 | 58 | 49 | 38 | 30 | 24 | 40 |
| Precip in | 1.7 | 1.3 | 1.3 | 1.1 | 1.5 | 0.8 | 0.2 | 0.2 | 0.5 | 0.9 | 1.3 | 2.0 | 12.8 |
1996–2025 normals for Payette County — the climate division New Plymouth sits in. All-time county record high 108.7°F (2002-07-12); record low -20.4°F (1962-01-22). Source: NOAA / National Weather Service.