Williamstown climate

Williamstown Weather in September

NOAA 1991-2020 normals for North Adams Harriman AP, 3.3 km from Williamstown

Average highs run from 77°F on September 1 to 67°F on September 30, and lows from 53°F to 44°F. Normal precipitation for the month is 4.22 in over about 12 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 Williamstown, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
72°F
Average low
49°F
Precipitation
4.22 in
Record high
92°FSep 1, 2010
Record low
28°FSep 29, 2000
Chance of a freeze
32%
Daylight
13 h 09 min to 11 h 47 min
Cloud cover
57%
Humidity
76%
Dew point
52°F
Wind
4.0 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 177°F53°F92°F 201039°F 201742%0%
Sep 277°F53°F92°F 201034°F 201742%0%
Sep 376°F53°F90°F 201840°F 202442%0%
Sep 476°F53°F88°F 199943°F 199742%0%
Sep 576°F52°F90°F 201838°F 200042%0%
Sep 675°F52°F88°F 202338°F 200042%0%
Sep 775°F52°F92°F 202336°F 198842%0%
Sep 875°F51°F90°F 201539°F 198842%0%
Sep 975°F51°F89°F 200238°F 201341%0%
Sep 1074°F51°F88°F 200241°F 200941%0%
Sep 1174°F50°F92°F 201336°F 201241%0%
Sep 1274°F50°F85°F 200536°F 200641%0%
Sep 1373°F50°F87°F 200540°F 201441%0%
Sep 1473°F50°F86°F 200538°F 201441%0%
Sep 1573°F49°F85°F 202136°F 200141%0%
Sep 1672°F49°F86°F 201832°F 198841%0%
Sep 1772°F48°F84°F 201734°F 200741%0%
Sep 1872°F48°F82°F 201535°F 202041%0%
Sep 1971°F48°F83°F 202430°F 202041%0%
Sep 2071°F47°F83°F 199830°F 202041%0%
Sep 2170°F47°F83°F 199828°F 202041%0%
Sep 2270°F47°F84°F 201931°F 202041%0%
Sep 2370°F46°F85°F 201935°F 201441%0%
Sep 2469°F46°F89°F 201032°F 199741%0%
Sep 2569°F46°F88°F 201733°F 199741%0%
Sep 2668°F45°F88°F 201732°F 201642%0%
Sep 2768°F45°F86°F 201736°F 200042%0%
Sep 2867°F45°F82°F 201430°F 200042%0%
Sep 2967°F44°F79°F 201528°F 200042%0%
Sep 3067°F44°F78°F 201032°F 200042%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Williamstown, in percent, and of at least 0.1 inch of snowfall.010203040501102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (EDT).

September 1
sunrise 6:18 AM, sunset 7:27 PM
September 30
sunrise 6:49 AM, sunset 6:36 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00054768 (North Adams Harriman AP), public domain. Records: NOAA GHCN-Daily, station USW00054768, 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.