The township has a humid continental climate (Dfa/Dfb) and the hardiness zones are 6a and 6b.

Average monthly temperatures in Seiberlingville range from 27.9 °F (−2.3 °C) in January to 71.6 °F (22.0 °C) in July.

As of the census of 2000,[5] there were 4,144 people, 1,458 households, and 1,214 families residing in the township.

11.8% of all households were made up of individuals, and 3.8% had someone living alone who was 65 years of age or older.

Weisenburg was named for the city of Weissenburg (now Wissembourg), a fortress and town in Alsace, from the region in which the majority of the townspeople had come.

[8] The township is served by the Northwestern Lehigh School District.

Emergency medical services are provided by the Cetronia Ambulance Corps, who have a unit stationed at the Weisenberg Township Volunteer Fire Department.