The official National Weather Service forecast for Plainview — 36.1773°N, 83.7953°W, 11.9 miles from I-40.
| Union County | J | F | M | A | M | J | J | A | S | O | N | D | Year |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high °F | 46 | 51 | 60 | 70 | 77 | 84 | 86 | 86 | 81 | 70 | 59 | 49 | 68 |
| Avg low °F | 27 | 31 | 37 | 44 | 53 | 61 | 66 | 64 | 58 | 46 | 36 | 31 | 46 |
| Precip in | 4.7 | 5.2 | 4.9 | 4.6 | 4.1 | 4.1 | 4.7 | 3.7 | 4.0 | 3.5 | 3.8 | 5.4 | 52.7 |
1996–2025 normals for Union County — the climate division Plainview sits in. All-time county record high 103.7°F (2012-07-01); record low -18.0°F (1985-01-21). Source: NOAA / National Weather Service.