The official National Weather Service forecast for Swansboro — 34.6877°N, 77.1191°W, population 20,542, 44.9 miles from I-40. Forecasts here are written by NWS MHX, this county’s forecast office.
| Onslow County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 56 | 59 | 66 | 74 | 80 | 86 | 89 | 88 | 83 | 75 | 66 | 59 | 73 |
| Avg low °F | 34 | 37 | 42 | 50 | 59 | 67 | 71 | 70 | 65 | 53 | 43 | 37 | 52 |
| Precip in | 3.4 | 3.5 | 3.6 | 3.6 | 4.6 | 5.3 | 6.7 | 7.1 | 7.5 | 3.6 | 3.3 | 3.9 | 56.1 |
1996–2025 normals for Onslow County — the climate division Swansboro sits in. All-time county record high 102.4°F (1952-06-27); record low -1.9°F (1985-01-21). Source: NOAA / National Weather Service.