Chapel Hill, NC frost dates
From NOAA weather station Chapel Hill Williams AP (USW00093785), elevation 512 ft. The station is named for Chapel Hill, and its coordinates are 1.3 miles from the Census Bureau’s internal point for Chapel Hill town.
Summary
In the 1991–2020 record, the median last spring freeze (32°F) at Chapel Hill Williams AP is Mar 29 and the median first fall freeze is Nov 5, for a typical freeze-free season of 222 days. In about 1 year in 10 the last spring freeze comes after Apr 12, and in about 1 year in 10 the first fall freeze arrives by Oct 23. The station averages 68 nights per year with a low of 32°F or colder.
Compared with the median of 187 North Carolina stations in this dataset, the median last freeze here is 3 days earlier than the state median (Apr 1), the median first freeze is 1 day later than the state median (Nov 4), and the growing season ranks #71 of 187 by length (longest = #1). The spread between the 90% and 10% spring dates is 32 days, a measure of how variable spring is here.
Freeze probability table
| Threshold | Last spring occurrence | First fall occurrence | Season length (days) 90% / 50% / 10% | ||||
|---|---|---|---|---|---|---|---|
| Early (90% chance of a later freeze) | Median (50%) | Cautious (10% chance of a later freeze) | Early (10% chance by then) | Median (50%) | Late (90% chance by then) | ||
| 36°F (light frost possible) | Mar 27 | Apr 11 | Apr 29 | Oct 15 | Oct 28 | Nov 8 | 178 / 199 / 219 |
| 32°F (freeze) | Mar 11 | Mar 29 | Apr 12 | Oct 23 | Nov 5 | Nov 21 | 202 / 222 / 246 |
| 28°F (hard freeze) | Feb 24 | Mar 15 | Apr 2 | Nov 2 | Nov 17 | Dec 10 | 223 / 248 / 276 |
Read the spring “Cautious” column as the safer planting date: only about 1 year in 10 has a freeze after it. NOAA computes these from daily minimum temperatures at the station; your yard can differ, especially in low spots or at a different elevation.
Planting calendar for Chapel Hill
Pick how much frost risk you accept. The calendar applies generic, extension-published timing rules to this station’s dates. See the rules and sources.
| Crop | Start seeds indoors | Plant outdoors (spring) | Latest fall planting (est.) | Days to harvest |
|---|
Fall estimates count back from the median first fall freeze (32°F for tender crops, 28°F hard freeze for cool-season crops) by the longer days-to-harvest figure. These are rough planning aids, not recommendations for any specific variety; check seed packets and your county extension office.
Towns that use this station as their nearest
Census places within 15 miles whose closest station in this dataset is Chapel Hill Williams AP: Chapel Hill (1 mi).
Nearby stations
- Chapel Hill 2 W, NC — 2 mi; median last freeze Mar 31, first freeze Nov 3
- Durham 11 W, NC — 3 mi; median last freeze Mar 31, first freeze Nov 4
- Durham, NC — 9 mi; median last freeze Apr 2, first freeze Nov 4
- Cane Creek Rsvr, NC — 10 mi; median last freeze Apr 6, first freeze Nov 1
- Chatham WTP, NC — 14 mi; median last freeze Apr 1, first freeze Nov 7
About this station’s data
- Station ID: USW00093785 · Latitude 35.9333, longitude -79.0642 · Elevation 156 m (512 ft)
- NOAA completeness flag: R — Representative: meets WMO standards for 10 or more years; gaps filled from surrounding stations. Years of data used: 17.
- Source file: USW00093785.csv (NOAA NCEI 1991–2020 annual/seasonal normals).
Raw values from the NOAA file (32°F)
| Field | Value |
|---|---|
ANN-TMIN-PRBLST-T32FP10 | 04/12 |
ANN-TMIN-PRBLST-T32FP50 | 03/29 |
ANN-TMIN-PRBLST-T32FP90 | 03/11 |
ANN-TMIN-PRBFST-T32FP10 | 10/23 |
ANN-TMIN-PRBFST-T32FP50 | 11/05 |
ANN-TMIN-PRBFST-T32FP90 | 11/21 |
ANN-TMIN-PRBGSL-T32FP10 | 246.0 |
ANN-TMIN-PRBGSL-T32FP50 | 222.0 |
ANN-TMIN-PRBGSL-T32FP90 | 202.0 |