Frost dates for Manchester Airport, NH
At Manchester Airport, the median last spring frost (32°F) is Apr 21 and the median first fall frost is Oct 19, for a typical growing season of 180 days. For a 90% chance that the last frost has passed, wait until May 6. Nearby ZIP codes are in USDA hardiness zone 6a.
- Apr 21Last spring frost (median)50% chance of 32°F after this date
- May 6Safer planting date10% chance of 32°F after this date
- Oct 19First fall frost (median)50% chance of 32°F by this date
- 180 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 23 | May 4 | May 19 |
| 32°F | Apr 8 | Apr 21 | May 6 |
| 28°F | Mar 28 | Apr 7 | Apr 21 |
| 24°F | Mar 15 | Mar 29 | Apr 7 |
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 28 | Oct 7 | Oct 22 |
| 32°F | Oct 4 | Oct 19 | Nov 4 |
| 28°F | Oct 16 | Nov 1 | Nov 15 |
| 24°F | Nov 1 | Nov 15 | 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 | 139 days | 156 days | 172 days |
| 32°F | 160 days | 180 days | 198 days |
| 28°F | 186 days | 206 days | 224 days |
| 24°F | 212 days | 230 days | 250 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 |
|---|---|---|---|
| 03103 | 6a | -10 to -5°F | 3 km |
| 03110 | 6a | -10 to -5°F | 8 km |
| 03053 | 6a | -10 to -5°F | 8 km |
| 03045 | 6a | -10 to -5°F | 14 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 USW00014710, at 42.9333, -71.4383, elevation 69 m (225 ft).
- Data quality: Representative (10+ years), 23 years of freeze data.
- Average days per year at or below 32°F: 129.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Massabesic Lake (7 km)
- Nashua 2 NNW (16 km)
- Hudson 1 SSE (17 km)
- E Milford (19 km)
- W Hampstead (19 km)
- Milford (20 km)
- Nashua Cwsu (22 km)
- Concord Muni Airport (30 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.