The official National Weather Service forecast for Spencer — 38.802°N, 81.3509°W, 16.5 miles from I-79.
| Roane County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 42 | 47 | 56 | 68 | 76 | 82 | 85 | 84 | 79 | 68 | 57 | 47 | 66 |
| Avg low °F | 23 | 27 | 33 | 41 | 50 | 59 | 63 | 62 | 56 | 44 | 33 | 28 | 43 |
| Precip in | 3.4 | 3.3 | 3.9 | 4.0 | 4.8 | 5.0 | 5.1 | 3.8 | 3.3 | 3.1 | 2.9 | 3.6 | 46.2 |
1996–2025 normals for Roane County — the climate division Spencer sits in. All-time county record high 101.9°F (1988-07-17); record low -23.8°F (1994-01-20). Source: NOAA / National Weather Service.