All Philadelphia School District schools, early childhood centers and offices will be closed Monday, spokesman Fernando Gallard said.
Officials made the call Sunday afternoon after consulting with city officials.
The Archdiocese of Philadelphia announced all Catholic high schools and elementary schools in the city would also be closed because of "ongoing travel difficulties."
Though it's the first inclement-weather day of the term for Philadelphia students, the day must be made up.
Because of a higher-than-usual number of days off earlier in the year due to the Pope's September visit, there were no snow days built into the calendar.
An extra day will be tacked onto the school calendar: students' final day is now June 23, not June 22 as initially ordered by the School Reform Commission.
A spokesman for the archdiocese said suburban schools usually follow the decisions of their corresponding local public school districts and announce their decisions independently.