The official National Weather Service forecast for Oswego — 37.1676°N, 95.11°W, 93 miles from I-35.
| Labette County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 45 | 50 | 60 | 69 | 77 | 86 | 91 | 90 | 83 | 72 | 59 | 48 | 69 |
| Avg low °F | 24 | 28 | 37 | 46 | 56 | 66 | 70 | 68 | 60 | 48 | 37 | 28 | 47 |
| Precip in | 1.6 | 1.8 | 3.3 | 4.4 | 6.6 | 5.6 | 3.5 | 4.1 | 3.8 | 4.0 | 2.6 | 1.9 | 43.2 |
1996–2025 normals for Labette County — the climate division Oswego sits in. All-time county record high 114.6°F (1954-07-14); record low -16.4°F (2011-02-10). Source: NOAA / National Weather Service.