Frost dates for Trenton State College, NJ
At Trenton State College, the median last spring frost (32°F) is Apr 17 and the median first fall frost is Oct 28, for a typical growing season of 192 days. For a 90% chance that the last frost has passed, wait until May 6. Nearby ZIP codes are in USDA hardiness zones 7a to 7b.
- Apr 17Last spring frost (median)50% chance of 32°F after this date
- May 6Safer planting date10% chance of 32°F after this date
- Oct 28First fall frost (median)50% chance of 32°F by this date
- 192 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 16 | May 1 | May 17 |
| 32°F | Apr 2 | Apr 17 | May 6 |
| 28°F | Mar 18 | Apr 2 | Apr 17 |
| 24°F | Mar 4 | Mar 21 | Apr 5 |
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 1 | Oct 15 | Oct 30 |
| 32°F | Oct 11 | Oct 28 | Nov 10 |
| 28°F | Oct 25 | Nov 7 | Nov 24 |
| 24°F | Nov 3 | Nov 20 | Dec 5 |
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 | 144 days | 165 days | 187 days |
| 32°F | 168 days | 192 days | 214 days |
| 28°F | 197 days | 217 days | 241 days |
| 24°F | 220 days | 243 days | 267 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 |
|---|---|---|---|
| 08618 | 7b | 5 to 10°F | 2 km |
| 08638 | 7a | 0 to 5°F | 3 km |
| 08648 | 7a | 0 to 5°F | 6 km |
| 08609 | 7a | 0 to 5°F | 7 km |
| 08629 | 7a | 0 to 5°F | 8 km |
| 08619 | 7a | 0 to 5°F | 9 km |
| 19030 | 7a | 0 to 5°F | 11 km |
| 08611 | 7a | 0 to 5°F | 11 km |
| 08610 | 7a | 0 to 5°F | 11 km |
| 19054 | 7a | 0 to 5°F | 11 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 USC00288880, at 40.2714, -74.7919, elevation 30 m (100 ft).
- Data quality: Representative (10+ years), 11 years of freeze data.
- Average days per year at or below 32°F: 109.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Trenton Mercer Co Airport (2 km)
- Lambertville (16 km)
- Hightstown 2 W (19 km)
- Wertsville 4 NE (20 km)
- Philadelphia/mt Holly WFO (29 km)
- Flemington 5 NNW (34 km)
- Mount Holly S Jersey Airport (36 km)
- New Brunswick 3 SE (38 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.