Frost dates for Boston 4 SE, VA
At Boston 4 SE, the median last spring frost (32°F) is Apr 21 and the median first fall frost is Oct 22, for a typical growing season of 184 days. For a 90% chance that the last frost has passed, wait until May 10. Nearby ZIP codes are in USDA hardiness zone 7a.
- Apr 21Last spring frost (median)50% chance of 32°F after this date
- May 10Safer planting date10% chance of 32°F after this date
- Oct 22First fall frost (median)50% chance of 32°F by this date
- 184 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 19 | May 3 | May 20 |
| 32°F | Apr 5 | Apr 21 | May 10 |
| 28°F | Mar 23 | Apr 5 | Apr 23 |
| 24°F | Mar 8 | Mar 25 | Apr 6 |
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 | Oct 2 | Oct 13 | Oct 25 |
| 32°F | Oct 8 | Oct 22 | Nov 4 |
| 28°F | Oct 17 | Nov 1 | Nov 15 |
| 24°F | Oct 30 | Nov 11 | Dec 1 |
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 | 143 days | 162 days | 181 days |
| 32°F | 162 days | 184 days | 205 days |
| 28°F | 187 days | 208 days | 230 days |
| 24°F | 211 days | 233 days | 258 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 |
|---|---|---|---|
| 22713 | 7a | 0 to 5°F | 4 km |
| 22716 | 7a | 0 to 5°F | 9 km |
| 22737 | 7a | 0 to 5°F | 10 km |
| 22735 | 7a | 0 to 5°F | 10 km |
| 22746 | 7a | 0 to 5°F | 11 km |
| 22725 | 7a | 0 to 5°F | 13 km |
| 22722 | 7a | 0 to 5°F | 14 km |
| 22701 | 7a | 0 to 5°F | 15 km |
| 22715 | 7a | 0 to 5°F | 16 km |
| 22714 | 7a | 0 to 5°F | 18 km |
| 20106 | 7a | 0 to 5°F | 19 km |
| 22741 | 7a | 0 to 5°F | 23 km |
| 22726 | 7a | 0 to 5°F | 29 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 USC00440860, at 38.5458, -78.0981, elevation 180 m (590 ft).
- Data quality: Representative (10+ years), 16 years of freeze data.
- Average days per year at or below 32°F: 121.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Sperryville (17 km)
- Luray 5 E (27 km)
- Big Meadows (29 km)
- Warrenton 3 SE (32 km)
- Piedmont Rsch Station (35 km)
- Somerset (37 km)
- Front Royal (40 km)
- Woodstock 2 NE (51 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.