Climate

Princeton weather by month

Average highs, lows, rain and snow for every month, from 30 years of weather records.

Average temperatures

Best time to visit: May, September, October, when highs are mild and rain is lightest.

Month	High	Low	Rain	Snow	Wet days
January	40°F	24°F	3.3 in	8.2 in	10
February	43°F	26°F	2.6 in	8.7 in	10
March	51°F	33°F	4.0 in	4.0 in	11
April	63°F	42°F	3.6 in	0.50 in	12
May	72°F	52°F	4.0 in	0.00 in	12
June	81°F	61°F	4.3 in	0.00 in	12
July	86°F	67°F	4.4 in	0.00 in	11
August	84°F	65°F	4.2 in	0.00 in	10
September	77°F	58°F	4.0 in	0.00 in	9
October	66°F	46°F	3.8 in	0.10 in	10
November	55°F	36°F	3.2 in	0.50 in	9
December	44°F	29°F	4.0 in	4.6 in	11

NOAA U.S. Climate Normals 1991–2020, Trenton Mercer Co Ap, Nj Us (9.7 mi away, 184 ft). Wet days: days with at least 0.01 in of precipitation.

What is the hottest month in Princeton?

July, with an average high of 86°F and low of 67°F.

What is the coldest month in Princeton?

January, with an average low of 24°F and high of 40°F.

When does it rain most in Princeton?

July is the wettest month, averaging 4.4 in of precipitation; the year totals about 45.4 inches.

Does it snow in Princeton?

Yes. Snowfall averages about 27 inches a year, mostly in February and January.

What is the best time to visit Princeton?

For mild weather (highs between 65°F and 85°F) with the least rain, May, September, October.

Where do these numbers come from?

NOAA’s 1991–2020 U.S. Climate Normals for the Trenton Mercer Co Ap weather station, 9.7 miles from downtown: 30-year averages, not a forecast.