Currently: 87 °F. Scattered clouds. (Weather station: Philadelphia International Airport, USA). See more current weatherAnnual Weather Averages Near Williamstown
Averages are for Philadelphia International Airport, which is 18 miles from Williamstown.
Based on weather reports collected during 1992–2021.
All Year Climate & Weather Averages in Williamstown
High Temp: 88 °F
Low Temp: 27 °F
Mean Temp: 57 °F
Precipitation: 3.70"
Humidity: 63%
Dew Point: 44 °F
Wind: 15 mph
Pressure: 30.05 "Hg
Visibility: 9 mi
January Climate & Weather Averages in Williamstown
High Temp: 41 °F
Low Temp: 27 °F
Mean Temp: 34 °F
Precipitation: 3.03"
Humidity: 63%
Dew Point: 22 °F
Wind: 16 mph
Pressure: 30.10 "Hg
Visibility: 9 mi
February Climate & Weather Averages in Williamstown
High Temp: 44 °F
Low Temp: 28 °F
Mean Temp: 36 °F
Precipitation: 2.90"
Humidity: 60%
Dew Point: 23 °F
Wind: 17 mph
Pressure: 30.09 "Hg
Visibility: 9 mi
March Climate & Weather Averages in Williamstown
High Temp: 53 °F
Low Temp: 35 °F
Mean Temp: 44 °F
Precipitation: 3.98"
Humidity: 58%
Dew Point: 29 °F
Wind: 17 mph
Pressure: 30.08 "Hg
Visibility: 9 mi
April Climate & Weather Averages in Williamstown
High Temp: 64 °F
Low Temp: 45 °F
Mean Temp: 55 °F
Precipitation: 3.48"
Humidity: 57%
Dew Point: 39 °F
Wind: 17 mph
Pressure: 30.00 "Hg
Visibility: 9 mi
May Climate & Weather Averages in Williamstown
High Temp: 74 °F
Low Temp: 55 °F
Mean Temp: 64 °F
Precipitation: 3.41"
Humidity: 62%
Dew Point: 50 °F
Wind: 14 mph
Pressure: 30.01 "Hg
Visibility: 9 mi
June Climate & Weather Averages in Williamstown
High Temp: 83 °F
Low Temp: 65 °F
Mean Temp: 74 °F
Precipitation: 4.04"
Humidity: 64%
Dew Point: 61 °F
Wind: 14 mph
Pressure: 29.97 "Hg
Visibility: 9 mi
July Climate & Weather Averages in Williamstown
High Temp: 88 °F
Low Temp: 70 °F
Mean Temp: 79 °F
Precipitation: 4.47"
Humidity: 64%
Dew Point: 65 °F
Wind: 13 mph
Pressure: 29.97 "Hg
Visibility: 9 mi
August Climate & Weather Averages in Williamstown
High Temp: 86 °F
Low Temp: 69 °F
Mean Temp: 77 °F
Precipitation: 4.38"
Humidity: 66%
Dew Point: 64 °F
Wind: 12 mph
Pressure: 30.01 "Hg
Visibility: 9 mi
September Climate & Weather Averages in Williamstown
High Temp: 79 °F
Low Temp: 62 °F
Mean Temp: 70 °F
Precipitation: 4.44"
Humidity: 67%
Dew Point: 59 °F
Wind: 13 mph
Pressure: 30.06 "Hg
Visibility: 9 mi
October Climate & Weather Averages in Williamstown
High Temp: 67 °F
Low Temp: 50 °F
Mean Temp: 59 °F
Precipitation: 3.56"
Humidity: 67%
Dew Point: 47 °F
Wind: 14 mph
Pressure: 30.08 "Hg
Visibility: 9 mi
November Climate & Weather Averages in Williamstown
High Temp: 56 °F
Low Temp: 39 °F
Mean Temp: 48 °F
Precipitation: 2.88"
Humidity: 64%
Dew Point: 35 °F
Wind: 15 mph
Pressure: 30.13 "Hg
Visibility: 9 mi
December Climate & Weather Averages in Williamstown
High Temp: 46 °F
Low Temp: 32 °F
Mean Temp: 39 °F
Precipitation: 3.85"
Humidity: 65%
Dew Point: 28 °F
Wind: 15 mph
Pressure: 30.12 "Hg
Visibility: 9 mi