The Allentown, Pennsylvania, school district decided to close schools in the area out of an “abundance of caution” ahead of Trump’s rally there this afternoon.

“This event is expected to bring large crowds, heavy traffic, and potential disruptions that may impact the safety and security of our students and staff,” an email from the school district’s communication office said.

Trump is scheduled to appear in Allentown at 7 p.m., and doors open at 3 p.m. Pennsylvania has been the state to watch as Harris and Trump battle for its 19 electoral votes. The two are locked in a tight race, with FiveThirtyEight giving Trump a 0.2-point advantage in the state.

The state also has a sizable Puerto Rican population, which has made headlines since a comedian made an offensive joke at Trump’s Madison Square Garden rally, calling the U.S. territory an “island of garbage.” Almost 10% of residents in Allentown are Puerto Rican.