ALLENTOWN (AP) — National Weather Service investigators will try to determine if a tornado touched down in Pennsylvania.

A survey team on Monday will examine damage left behind as a severe storm moved through Allentown’s Heidelberg Township suburb on Sunday. A portion of a barn roof was torn off and trees were downed in the Lehigh County community.

A firefighter posted a video which appears to show a funnel cloud forming.

The weather service confirmed two tornadoes struck northeast Pennsylvania last month, injuring six people and damaging more than a dozen businesses.

Heavy downpours are possible throughout the state on Monday.