The official National Weather Service forecast for Forest Lake — 45.2789°N, 92.9852°W, population 21,882, 4.5 miles from I-35. Forecasts here are written by NWS MPX, this county’s forecast office.
| Washington County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 23 | 28 | 41 | 56 | 69 | 78 | 83 | 80 | 73 | 58 | 43 | 28 | 55 |
| Avg low °F | 7 | 10 | 22 | 35 | 47 | 58 | 62 | 60 | 53 | 39 | 27 | 14 | 36 |
| Precip in | 0.8 | 0.9 | 1.8 | 2.9 | 4.2 | 4.7 | 3.8 | 4.5 | 3.1 | 2.6 | 1.5 | 1.3 | 32.1 |
1996–2025 normals for Washington County — the climate division Forest Lake sits in. All-time county record high 102.0°F (1988-08-01); record low -36.6°F (1951-01-30). Source: NOAA / National Weather Service.