The official National Weather Service forecast for Monticello — 30.5451°N, 83.8713°W, 5.8 miles from I-10. Forecasts here are written by NWS TAE, this county’s forecast office.
| Jefferson County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 64 | 68 | 74 | 80 | 87 | 91 | 92 | 91 | 88 | 81 | 73 | 66 | 80 |
| Avg low °F | 40 | 44 | 49 | 55 | 63 | 70 | 72 | 72 | 68 | 58 | 48 | 43 | 57 |
| Precip in | 3.9 | 4.0 | 4.6 | 4.0 | 3.0 | 6.5 | 6.6 | 6.4 | 5.3 | 2.8 | 2.7 | 3.8 | 53.6 |
1996–2025 normals for Jefferson County — the climate division Monticello sits in. All-time county record high 102.3°F (1998-06-19); record low 5.7°F (1985-01-21). Source: NOAA / National Weather Service.