Frost dates for Blacksburg NWSO, VA
At Blacksburg NWSO, the median last spring frost (32°F) is Apr 24 and the median first fall frost is Oct 19, for a typical growing season of 175 days. For a 90% chance that the last frost has passed, wait until May 14. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 24Last spring frost (median)50% chance of 32°F after this date
- May 14Safer planting date10% chance of 32°F after this date
- Oct 19First fall frost (median)50% chance of 32°F by this date
- 175 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Apr 21 | May 6 | May 24 |
| 32°F | Apr 11 | Apr 24 | May 14 |
| 28°F | Mar 28 | Apr 11 | Apr 27 |
| 24°F | Mar 14 | Mar 30 | Apr 13 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 26 | Oct 8 | Oct 21 |
| 32°F | Oct 6 | Oct 19 | Nov 1 |
| 28°F | Oct 15 | Oct 29 | Nov 8 |
| 24°F | Oct 24 | Nov 5 | Nov 22 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 134 days | 155 days | 173 days |
| 32°F | 154 days | 175 days | 196 days |
| 28°F | 178 days | 199 days | 218 days |
| 24°F | 203 days | 220 days | 243 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 24061 | 7a | 0 to 5°F | 3 km |
| 24060 | 7a | 0 to 5°F | 6 km |
| 24087 | 7b | 5 to 10°F | 16 km |
| 24128 | 7a | 0 to 5°F | 16 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00440766, at 37.2039, -80.4144, elevation 641 m (2,103 ft).
- Data quality: Standard (24+ years of data), 26 years of freeze data.
- Average days per year at or below 32°F: 125.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Christiansburg (9 km)
- Radford 3 N (15 km)
- Pearisburg 4 SSE (26 km)
- Copper Hill (28 km)
- Floyd 2 NE (33 km)
- Pulaski 2 E (37 km)
- Roanoke Regional Airport (41 km)
- Roanoke 8 N (44 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.