Frost dates for Boston Logan Intl Airport, MA
At Boston Logan Intl Airport, the median last spring frost (32°F) is Apr 4 and the median first fall frost is Nov 9, for a typical growing season of 218 days. For a 90% chance that the last frost has passed, wait until Apr 17. Nearby ZIP codes are in USDA hardiness zones 6b to 7a.
- Apr 4Last spring frost (median)50% chance of 32°F after this date
- Apr 17Safer planting date10% chance of 32°F after this date
- Nov 9First fall frost (median)50% chance of 32°F by this date
- 218 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 6 | Apr 17 | May 1 |
| 32°F | Mar 25 | Apr 4 | Apr 17 |
| 28°F | Mar 15 | Mar 28 | Apr 6 |
| 24°F | Mar 6 | Mar 19 | Apr 1 |
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 15 | Oct 29 | Nov 11 |
| 32°F | Oct 29 | Nov 9 | Nov 22 |
| 28°F | Nov 8 | Nov 21 | Dec 5 |
| 24°F | Nov 16 | Dec 1 | Dec 18 |
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 | 175 days | 194 days | 210 days |
| 32°F | 201 days | 218 days | 235 days |
| 28°F | 221 days | 239 days | 258 days |
| 24°F | 239 days | 258 days | 278 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 |
|---|---|---|---|
| 02128 | 7a | 0 to 5°F | 0 km |
| 02210 | 7a | 0 to 5°F | 3 km |
| 02152 | 7a | 0 to 5°F | 3 km |
| 02109 | 7a | 0 to 5°F | 3 km |
| 02110 | 7a | 0 to 5°F | 3 km |
| 02127 | 7a | 0 to 5°F | 4 km |
| 02113 | 7a | 0 to 5°F | 4 km |
| 02205 | 7a | 0 to 5°F | 4 km |
| 02203 | 7a | 0 to 5°F | 4 km |
| 02111 | 7a | 0 to 5°F | 4 km |
| 02150 | 7a | 0 to 5°F | 4 km |
| 02133 | 7a | 0 to 5°F | 4 km |
| 02108 | 7a | 0 to 5°F | 5 km |
| 02114 | 7a | 0 to 5°F | 5 km |
| 02129 | 7a | 0 to 5°F | 5 km |
| 02118 | 7a | 0 to 5°F | 5 km |
| 02116 | 7a | 0 to 5°F | 6 km |
| 02142 | 7a | 0 to 5°F | 6 km |
| 02141 | 7a | 0 to 5°F | 6 km |
| 02149 | 7a | 0 to 5°F | 6 km |
| 02151 | 7a | 0 to 5°F | 6 km |
| 02145 | 7a | 0 to 5°F | 7 km |
| 02143 | 7a | 0 to 5°F | 7 km |
| 02171 | 7a | 0 to 5°F | 8 km |
| 02148 | 6b | -5 to 0°F | 9 km |
| 02144 | 6b | -5 to 0°F | 10 km |
| 02155 | 6b | -5 to 0°F | 11 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 USW00014739, at 42.3606, -71.0106, elevation 4 m (12 ft).
- Data quality: Standard (24+ years of data), 28 years of freeze data.
- Average days per year at or below 32°F: 92.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Jamaica Plain (11 km)
- Hingham (17 km)
- Blue Hill COOP (19 km)
- Blue Hill (19 km)
- Marblehead (20 km)
- Reading (20 km)
- Norwood Mem Airport (23 km)
- Middleton (26 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.