Public schools in Philadelphia are closing early Tuesday because of the heat and high humidity.The Philadelphia School District said its schools will close at 1:30 p.m. and all after-school programs are canceled. Regular transportation will be available for all students, according to the district. Staff will remain in buildings until all students have left or been picked up, the district said. Updated information will be available on the district’s information hot line at 215-400-INFO (4636) or on its website, philasd.org.