Frost dates for Jaffrey Silver Rch Airpark, NH
At Jaffrey Silver Rch Airpark, the median last spring frost (32°F) is May 5 and the median first fall frost is Oct 6, for a typical growing season of 154 days. For a 90% chance that the last frost has passed, wait until May 19. Nearby ZIP codes are in USDA hardiness zone 6a.
- May 5Last spring frost (median)50% chance of 32°F after this date
- May 19Safer planting date10% chance of 32°F after this date
- Oct 6First fall frost (median)50% chance of 32°F by this date
- 154 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 3 | May 17 | May 31 |
| 32°F | Apr 22 | May 5 | May 19 |
| 28°F | Apr 7 | Apr 21 | May 6 |
| 24°F | Mar 29 | Apr 8 | Apr 20 |
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 15 | Sep 28 | Oct 9 |
| 32°F | Sep 25 | Oct 6 | Oct 22 |
| 28°F | Oct 3 | Oct 19 | Nov 5 |
| 24°F | Oct 15 | Nov 2 | Nov 17 |
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 | 114 days | 132 days | 149 days |
| 32°F | 135 days | 154 days | 175 days |
| 28°F | 158 days | 179 days | 202 days |
| 24°F | 183 days | 207 days | 226 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 |
|---|---|---|---|
| 03452 | 6a | -10 to -5°F | 5 km |
| 03458 | 6a | -10 to -5°F | 8 km |
| 03444 | 6a | -10 to -5°F | 10 km |
| 03465 | 6a | -10 to -5°F | 15 km |
| 03450 | 6a | -10 to -5°F | 16 km |
| 03047 | 6a | -10 to -5°F | 18 km |
| 03449 | 6a | -10 to -5°F | 19 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 USC00274304, at 42.8089, -72.0053, elevation 314 m (1,030 ft).
- Data quality: Estimated from nearby stations (2+ years), 8 years of freeze data.
- Average days per year at or below 32°F: 150.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Jaffrey Muni Airport (0 km)
- Greenville 1 NNE (17 km)
- Milford (29 km)
- Keene (30 km)
- E Milford (31 km)
- Weare (38 km)
- Weare 2 NE (38 km)
- Walpole 2s Nepp (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.