The official National Weather Service forecast for Guernsey — 42.2697°N, 104.7416°W, 15.7 miles from I-25.
| Platte County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 40 | 40 | 51 | 58 | 67 | 80 | 88 | 86 | 77 | 62 | 50 | 40 | 62 |
| Avg low °F | 16 | 16 | 24 | 30 | 39 | 49 | 56 | 53 | 44 | 32 | 23 | 16 | 33 |
| Precip in | 0.4 | 0.5 | 1.0 | 1.8 | 2.5 | 1.7 | 1.4 | 1.2 | 1.2 | 1.1 | 0.5 | 0.5 | 13.8 |
1996–2025 normals for Platte County — the climate division Guernsey sits in. All-time county record high 101.8°F (2026-08-03); record low -33.2°F (1990-12-22). Source: NOAA / National Weather Service.