Frost dates for Rochester Skyhaven Airport, NH
At Rochester Skyhaven Airport, the median last spring frost (32°F) is Apr 30 and the median first fall frost is Oct 9, for a typical growing season of 161 days. For a 90% chance that the last frost has passed, wait until May 13. Nearby ZIP codes are in USDA hardiness zones 5b to 6a.
- Apr 30Last spring frost (median)50% chance of 32°F after this date
- May 13Safer planting date10% chance of 32°F after this date
- Oct 9First fall frost (median)50% chance of 32°F by this date
- 161 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 | May 1 | May 12 | May 25 |
| 32°F | Apr 18 | Apr 30 | May 13 |
| 28°F | Apr 4 | Apr 17 | Apr 29 |
| 24°F | Mar 23 | Apr 4 | Apr 17 |
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 17 | Sep 30 | Oct 12 |
| 32°F | Sep 27 | Oct 9 | Oct 25 |
| 28°F | Oct 7 | Oct 23 | Nov 7 |
| 24°F | Oct 21 | Nov 5 | Nov 21 |
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 | 120 days | 138 days | 155 days |
| 32°F | 142 days | 161 days | 181 days |
| 28°F | 168 days | 188 days | 208 days |
| 24°F | 194 days | 213 days | 233 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 |
|---|---|---|---|
| 03878 | 6a | -10 to -5°F | 4 km |
| 03839 | 6a | -10 to -5°F | 5 km |
| 03868 | 6a | -10 to -5°F | 5 km |
| 03867 | 6a | -10 to -5°F | 6 km |
| 03901 | 6a | -10 to -5°F | 7 km |
| 03835 | 6a | -10 to -5°F | 15 km |
| 03851 | 5b | -15 to -10°F | 20 km |
| 03884 | 6a | -10 to -5°F | 20 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 USW00054791, at 43.2781, -70.9222, elevation 98 m (323 ft).
- Data quality: Representative (10+ years), 21 years of freeze data.
- Average days per year at or below 32°F: 145.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Durham 2 N (12 km)
- Durham (15 km)
- Durham 2 SSW (19 km)
- Greenland (30 km)
- Epping (31 km)
- W Hampstead (47 km)
- Concord Muni Airport (48 km)
- Massabesic Lake (50 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.