Princeton climate

Princeton Weather in September

NOAA 1991-2020 normals for Smithfield, 17.5 km from Princeton

Average highs run from 87°F on September 1 to 80°F on September 30, and lows from 67°F to 58°F. Normal precipitation for the month is 5.51 in over about 9 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Princeton, in °F, with the record for each date.406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
84°F
Average low
63°F
Precipitation
5.51 in
Record high
97°FSep 3, 2026
Record low
46°FSep 24, 2022
Chance of a freeze
0%
Days of 90°F or more
4.9
Daylight
12 h 55 min to 11 h 51 min
Cloud cover
54%
Humidity
78%
Dew point
64°F
Wind
8.1 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 187°F67°F92°F 201856°F 202530%0%
Sep 287°F66°F94°F 202656°F 202530%0%
Sep 387°F66°F97°F 202654°F 202530%0%
Sep 487°F66°F95°F 202654°F 202530%0%
Sep 586°F66°F94°F 202656°F 202530%0%
Sep 686°F66°F93°F 202660°F 201629%0%
Sep 786°F66°F93°F 202359°F 201729%0%
Sep 886°F65°F92°F 202354°F 201729%0%
Sep 985°F65°F91°F 201654°F 201729%0%
Sep 1085°F65°F90°F 201654°F 202429%0%
Sep 1185°F65°F91°F 202654°F 201228%0%
Sep 1285°F64°F93°F 202653°F 201228%0%
Sep 1384°F64°F91°F 201953°F 201228%0%
Sep 1484°F64°F88°F 202152°F 201528%0%
Sep 1584°F64°F92°F 202651°F 201528%0%
Sep 1684°F63°F89°F 202152°F 201528%0%
Sep 1783°F63°F85°F 201954°F 201528%0%
Sep 1883°F63°F90°F 202652°F 201328%0%
Sep 1983°F62°F92°F 202552°F 201328%0%
Sep 2083°F62°F89°F 202552°F 201328%0%
Sep 2182°F62°F88°F 202253°F 202028%0%
Sep 2282°F61°F88°F 202250°F 202028%0%
Sep 2382°F61°F87°F 201848°F 202028%0%
Sep 2481°F60°F94°F 202546°F 202228%0%
Sep 2581°F60°F94°F 202547°F 202228%0%
Sep 2681°F60°F88°F 202546°F 202227%0%
Sep 2781°F59°F87°F 201848°F 202227%0%
Sep 2880°F59°F87°F 201752°F 202127%0%
Sep 2980°F58°F90°F 201751°F 202227%0%
Sep 3080°F58°F92°F 201952°F 202127%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Princeton, in percent, and of at least 0.1 inch of snowfall.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (EDT).

September 1
sunrise 6:45 AM, sunset 7:40 PM
September 30
sunrise 7:07 AM, sunset 6:58 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00317994 (Smithfield), public domain. Records: NOAA GHCN-Daily, station USC00313503, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.