Williamstown climate

Williamstown Weather in May

NOAA 1991-2020 normals for Dehart Dam, 17.3 km from Williamstown

Average highs run from 67°F on May 1 to 75°F on May 31, and lows from 42°F to 52°F. Normal precipitation for the month is 4.42 in over about 13 wet days.

May 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

May at a glance

Average high
71°F
Average low
47°F
Precipitation
4.42 in
Record high
95°FMay 18, 2026
Record low
27°FMay 4, 2005
Chance of a freeze
52%
Days of 90°F or more
0.7
Daylight
13 h 57 min to 14 h 52 min
Cloud cover
65%
Humidity
78%
Dew point
52°F
Wind
4.7 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
May 167°F42°F88°F 201030°F 197838%0%
May 268°F43°F87°F 201834°F 198638%0%
May 368°F43°F89°F 200130°F 196639%0%
May 468°F43°F89°F 200127°F 200539%0%
May 569°F43°F85°F 200029°F 197439%0%
May 669°F44°F87°F 200036°F 196639%0%
May 769°F44°F89°F 200030°F 196839%0%
May 869°F44°F89°F 200030°F 199739%0%
May 970°F45°F87°F 200028°F 197740%0%
May 1070°F45°F89°F 197929°F 196640%0%
May 1170°F45°F89°F 197027°F 196640%0%
May 1270°F46°F86°F 198734°F 198340%0%
May 1371°F46°F87°F 199132°F 196741%0%
May 1471°F46°F86°F 199130°F 199641%0%
May 1571°F47°F88°F 201830°F 199641%0%
May 1671°F47°F89°F 199835°F 198041%0%
May 1772°F47°F89°F 197732°F 198342%0%
May 1872°F48°F95°F 202634°F 197342%0%
May 1972°F48°F93°F 202632°F 197342%0%
May 2072°F48°F93°F 199637°F 197342%0%
May 2172°F49°F89°F 202231°F 200242%0%
May 2273°F49°F90°F 197532°F 200242%0%
May 2373°F49°F90°F 197537°F 199742%0%
May 2473°F50°F88°F 197038°F 200642%0%
May 2573°F50°F91°F 197541°F 200842%0%
May 2674°F50°F89°F 199138°F 197241%0%
May 2774°F51°F90°F 199137°F 197241%0%
May 2874°F51°F93°F 197736°F 199441%0%
May 2974°F51°F94°F 197740°F 200841%0%
May 3075°F52°F95°F 196937°F 199641%0%
May 3175°F52°F93°F 198738°F 199641%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).

May 1
sunrise 6:05 AM, sunset 8:02 PM
May 31
sunrise 5:38 AM, sunset 8:30 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00362071 (Dehart Dam), public domain. Records: NOAA GHCN-Daily, station USC00364896, 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.