The official National Weather Service forecast for Ionia — 42.9873°N, 85.0711°W, population 15,168, 8.8 miles from I-96. Forecasts here are written by NWS GRR, this county’s forecast office.
| Ionia County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 31 | 34 | 45 | 58 | 69 | 79 | 83 | 81 | 74 | 61 | 47 | 36 | 58 |
| Avg low °F | 17 | 17 | 25 | 35 | 46 | 56 | 60 | 58 | 51 | 40 | 31 | 23 | 38 |
| Precip in | 2.3 | 2.0 | 2.3 | 3.4 | 4.0 | 3.6 | 3.2 | 3.5 | 2.9 | 3.7 | 2.4 | 2.2 | 35.5 |
1996–2025 normals for Ionia County — the climate division Ionia sits in. All-time county record high 100.8°F (2012-07-07); record low -19.9°F (1981-01-04). Source: NOAA / National Weather Service.