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Will it freeze in Princeton in the next 7 nights?
No overnight lows at or below 32°F are forecast in Princeton during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 61°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
1 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 61°F Above 36°F · Light Rain Likely
- Fri, Nov 6 49°F Above 36°F · Partly Cloudy
- Sat, Nov 7 43°F Above 36°F · Partly Cloudy
- Sun, Nov 8 39°F Above 36°F · Mostly Clear
- Mon, Nov 9 37°F Above 36°F · Mostly Clear
- Tue, Nov 10 38°F Above 36°F · Mostly Clear
- Wed, Nov 11 34°F Frost possible · Partly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Princeton
The median first fall hard-freeze date (28°F) is October 28, from NOAA’s 1991–2020 Climate Normals at Hightstown 2 W. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | Apr 24 · May 8 · May 23 | Sep 26 · Oct 6 · Oct 19 | 151 days |
| 32°F freeze | Apr 12 · Apr 25 · May 12 | Oct 4 · Oct 16 · Oct 29 | 173 days |
| 28°F hard freeze | Mar 26 · Apr 10 · Apr 26 | Oct 13 · Oct 28 · Nov 11 | 200 days |
Average high temperature by month
1991–2020 normals at Hightstown 2 W
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Princeton, NJ come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Hightstown 2 W (station USC00283951, elevation 100 ft), 8.3 mi from Princeton. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Princeton
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Hightstown, NJ | 9.9 mi | Apr 25 | Oct 16 |
| Trenton, NJ | 11 mi | Apr 17 | Oct 28 |
| Jamesburg, NJ | 12 mi | Apr 15 | Oct 26 |
| Morrisville, PA | 12 mi | Apr 17 | Oct 28 |
| Manville, NJ | 13 mi | Apr 30 | Oct 20 |
| Milltown, NJ | 14 mi | Apr 15 | Oct 26 |
| Spotswood, NJ | 15 mi | Apr 15 | Oct 26 |
| New Brunswick, NJ | 15 mi | Apr 15 | Oct 26 |
| Raritan, NJ | 15 mi | Apr 30 | Oct 20 |
| Somerville, NJ | 15 mi | Apr 30 | Oct 20 |
Frequently asked questions
When is the last frost in Princeton?
On average, the last spring frost (32°F) in Princeton is around April 25. In about 1 year in 10 it comes after May 12, and in 9 years in 10 it comes after April 12.
When is the first frost in Princeton?
The first fall frost (32°F) usually arrives around October 16. There’s a 10% chance of a freeze by October 4 and a 90% chance by October 29.
Can it frost in Princeton after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 8.
What growing zone is Princeton?
Princeton is in USDA Plant Hardiness Zone 7a (average annual extreme minimum temperature 0 to 5°F), based on the 2023 USDA map for ZIP code 08542. See growing zones in New Jersey.
More: all New Jersey frost dates · New Jersey growing zones · UV index today in Princeton · frost vs. freeze