Frost dates for Burlington, CT
At Burlington, the median last spring frost (32°F) is Apr 25 and the median first fall frost is Oct 18, for a typical growing season of 172 days. For a 90% chance that the last frost has passed, wait until May 10. Nearby ZIP codes are in USDA hardiness zones 6a to 6b.
- Apr 25Last spring frost (median)50% chance of 32°F after this date
- May 10Safer planting date10% chance of 32°F after this date
- Oct 18First fall frost (median)50% chance of 32°F by this date
- 172 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 24 | May 6 | May 22 |
| 32°F | Apr 12 | Apr 25 | May 10 |
| 28°F | Apr 2 | Apr 13 | Apr 29 |
| 24°F | Mar 19 | Apr 2 | Apr 14 |
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 6 | Oct 20 |
| 32°F | Oct 4 | Oct 18 | Nov 1 |
| 28°F | Oct 14 | Oct 30 | Nov 14 |
| 24°F | Oct 26 | 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 | 131 days | 152 days | 170 days |
| 32°F | 151 days | 172 days | 192 days |
| 28°F | 175 days | 197 days | 217 days |
| 24°F | 202 days | 223 days | 245 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 |
|---|---|---|---|
| 06013 | 6a | -10 to -5°F | 5 km |
| 06085 | 6b | -5 to 0°F | 6 km |
| 06001 | 6b | -5 to 0°F | 6 km |
| 06019 | 6a | -10 to -5°F | 7 km |
| 06020 | 6a | -10 to -5°F | 8 km |
| 06032 | 6b | -5 to 0°F | 9 km |
| 06089 | 6b | -5 to 0°F | 10 km |
| 06010 | 6b | -5 to 0°F | 13 km |
| 06062 | 6b | -5 to 0°F | 15 km |
| 06786 | 6b | -5 to 0°F | 15 km |
| 06787 | 6a | -10 to -5°F | 19 km |
| 06782 | 6a | -10 to -5°F | 19 km |
| 06795 | 6b | -5 to 0°F | 25 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 USC00060973, at 41.7944, -72.9319, elevation 154 m (505 ft).
- Data quality: Representative (10+ years), 24 years of freeze data.
- Average days per year at or below 32°F: 142.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Bakersville (8 km)
- Barkhamsted (14 km)
- Hartford Brainard Field (24 km)
- Hartford Bradley Intl Airport (26 km)
- Norfolk 2 SW (31 km)
- Meriden Markham Muni Airport (33 km)
- Falls Village (40 km)
- Mount Carmel (43 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.