The official National Weather Service forecast for Johnson — 44.6356°N, 72.6804°W, 20.3 miles from I-89.
| Lamoille County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 25 | 28 | 37 | 50 | 64 | 72 | 76 | 75 | 68 | 55 | 42 | 31 | 52 |
| Avg low °F | 7 | 9 | 18 | 30 | 42 | 51 | 56 | 55 | 48 | 37 | 26 | 15 | 33 |
| Precip in | 3.0 | 2.8 | 3.3 | 4.0 | 4.2 | 5.3 | 4.9 | 4.4 | 3.8 | 4.8 | 3.7 | 4.1 | 48.3 |
1996–2025 normals for Lamoille County — the climate division Johnson sits in. All-time county record high 93.7°F (2025-06-24); record low -35.6°F (1957-01-15). Source: NOAA / National Weather Service.