The official National Weather Service forecast for Ossian — 40.8806°N, 85.1664°W, 8.7 miles from I-69. Forecasts here are written by NWS IWX, this county’s forecast office.
| Wells County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 33 | 37 | 49 | 62 | 72 | 81 | 84 | 82 | 77 | 65 | 50 | 39 | 61 |
| Avg low °F | 19 | 21 | 30 | 40 | 50 | 60 | 63 | 61 | 54 | 43 | 33 | 24 | 42 |
| Precip in | 2.6 | 2.3 | 3.0 | 3.8 | 4.6 | 4.5 | 4.3 | 3.8 | 3.0 | 2.9 | 2.8 | 2.7 | 40.3 |
1996–2025 normals for Wells County — the climate division Ossian sits in. All-time county record high 104.2°F (2012-06-29); record low -23.2°F (1985-01-20). Source: NOAA / National Weather Service.