Frost dates for Benton 5 SW, NH
At Benton 5 SW, the median last spring frost (32°F) is May 15 and the median first fall frost is Sep 28, for a typical growing season of 133 days. For a 90% chance that the last frost has passed, wait until Jun 3. Nearby ZIP codes are in USDA hardiness zones 4b to 5a.
- May 15Last spring frost (median)50% chance of 32°F after this date
- Jun 3Safer planting date10% chance of 32°F after this date
- Sep 28First fall frost (median)50% chance of 32°F by this date
- 133 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 15 | May 31 | Jun 14 |
| 32°F | May 1 | May 15 | Jun 3 |
| 28°F | Apr 18 | Apr 30 | May 16 |
| 24°F | Apr 6 | Apr 18 | Apr 29 |
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 2 | Sep 17 | Sep 30 |
| 32°F | Sep 12 | Sep 28 | Oct 9 |
| 28°F | Sep 25 | Oct 7 | Oct 23 |
| 24°F | Oct 4 | Oct 21 | Nov 7 |
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 | 85 days | 108 days | 128 days |
| 32°F | 110 days | 133 days | 154 days |
| 28°F | 138 days | 159 days | 180 days |
| 24°F | 165 days | 186 days | 206 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 |
|---|---|---|---|
| 03780 | 5a | -20 to -15°F | 3 km |
| 03238 | 5a | -20 to -15°F | 8 km |
| 03774 | 5a | -20 to -15°F | 8 km |
| 03765 | 5a | -20 to -15°F | 8 km |
| 03785 | 5a | -20 to -15°F | 8 km |
| 03779 | 5a | -20 to -15°F | 9 km |
| 03279 | 5a | -20 to -15°F | 10 km |
| 05051 | 5a | -20 to -15°F | 14 km |
| 05081 | 5a | -20 to -15°F | 16 km |
| 03740 | 5a | -20 to -15°F | 17 km |
| 05069 | 4b | -25 to -20°F | 22 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 USC00270681, at 44.0342, -71.9486, elevation 366 m (1,200 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 173.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Wentworth (19 km)
- Lincoln Nepp (22 km)
- Waterville Valley Nepp (36 km)
- Plymouth (37 km)
- Bethlehem 2 (38 km)
- Hanover (45 km)
- Whitefield Mount Washington Airport (49 km)
- Grafton (52 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.