Frost dates for Hartford Brainard Field, CT
At Hartford Brainard Field, the median last spring frost (32°F) is Apr 17 and the median first fall frost is Oct 26, for a typical growing season of 191 days. For a 90% chance that the last frost has passed, wait until May 1. Nearby ZIP codes are in USDA hardiness zone 6b.
- Apr 17Last spring frost (median)50% chance of 32°F after this date
- May 1Safer planting date10% chance of 32°F after this date
- Oct 26First fall frost (median)50% chance of 32°F by this date
- 191 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 17 | Apr 30 | May 14 |
| 32°F | Apr 1 | Apr 17 | May 1 |
| 28°F | Mar 21 | Apr 3 | Apr 21 |
| 24°F | Mar 8 | Mar 24 | 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 14 | Oct 29 |
| 32°F | Oct 12 | Oct 26 | Nov 7 |
| 28°F | Oct 22 | Nov 5 | Nov 20 |
| 24°F | Nov 2 | Nov 18 | Dec 2 |
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 | 148 days | 167 days | 186 days |
| 32°F | 169 days | 191 days | 212 days |
| 28°F | 193 days | 216 days | 237 days |
| 24°F | 215 days | 238 days | 260 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 |
|---|---|---|---|
| 06114 | 6b | -5 to 0°F | 2 km |
| 06103 | 6b | -5 to 0°F | 4 km |
| 06118 | 6b | -5 to 0°F | 4 km |
| 06106 | 6b | -5 to 0°F | 4 km |
| 06109 | 6b | -5 to 0°F | 4 km |
| 06108 | 6b | -5 to 0°F | 5 km |
| 06120 | 6b | -5 to 0°F | 6 km |
| 06105 | 6b | -5 to 0°F | 6 km |
| 06110 | 6b | -5 to 0°F | 7 km |
| 06119 | 6b | -5 to 0°F | 7 km |
| 06112 | 6b | -5 to 0°F | 7 km |
| 06111 | 6b | -5 to 0°F | 9 km |
| 06067 | 6b | -5 to 0°F | 9 km |
| 06107 | 6b | -5 to 0°F | 9 km |
| 06033 | 6b | -5 to 0°F | 10 km |
| 06040 | 6b | -5 to 0°F | 11 km |
| 06073 | 6b | -5 to 0°F | 11 km |
| 06117 | 6b | -5 to 0°F | 11 km |
| 06051 | 6b | -5 to 0°F | 13 km |
| 06053 | 6b | -5 to 0°F | 13 km |
| 06074 | 6b | -5 to 0°F | 13 km |
| 06042 | 6b | -5 to 0°F | 13 km |
| 06416 | 6b | -5 to 0°F | 13 km |
| 06052 | 6b | -5 to 0°F | 16 km |
| 06480 | 6b | -5 to 0°F | 16 km |
| 06414 | 6b | -5 to 0°F | 19 km |
| 06066 | 6b | -5 to 0°F | 19 km |
| 06447 | 6b | -5 to 0°F | 20 km |
| 06424 | 6b | -5 to 0°F | 23 km |
| 06456 | 6b | -5 to 0°F | 23 km |
| 06469 | 6b | -5 to 0°F | 31 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 USW00014752, at 41.7361, -72.6506, elevation 6 m (19 ft).
- Data quality: Standard (24+ years of data), 28 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
- Hartford Bradley Intl Airport (23 km)
- Burlington (24 km)
- Meriden Markham Muni Airport (29 km)
- Bakersville (32 km)
- Barkhamsted (33 km)
- Storrs (36 km)
- Willimantic Windham Airport (39 km)
- Mount Carmel (42 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.