The official National Weather Service forecast for Munster — 41.5645°N, 87.5125°W, 1.1 miles from I-94. Forecasts here are written by NWS LOT, this county’s forecast office.
| Lake County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 32 | 37 | 48 | 60 | 71 | 81 | 84 | 82 | 77 | 64 | 50 | 37 | 60 |
| Avg low °F | 17 | 20 | 29 | 38 | 49 | 59 | 63 | 61 | 54 | 43 | 32 | 23 | 41 |
| Precip in | 2.2 | 2.0 | 2.5 | 3.5 | 4.4 | 4.4 | 4.4 | 4.0 | 3.1 | 3.6 | 2.4 | 2.3 | 38.8 |
1996–2025 normals for Lake County — the climate division Munster sits in. All-time county record high 101.6°F (1988-08-17); record low -22.9°F (1985-01-20). Source: NOAA / National Weather Service.