Officials began recommending visitors to leave potentially affected areas by three days before Isabel made landfall. Governor Minner mandated all schools to be closed on the day of the hurricane's landfall, and recommended all residents in mobile homes to evacuate and for businesses to close. The University of Delaware preemptively canceled classes.
Before Isabel made landfall, officials advised people to leave areas that might be affected three days early. Governor Minner decreed that all schools would be closed on the day of the hurricane's arrival, and suggested that everyone living in mobile homes should evacuate and that businesses shut down. The University of Delaware cancelled its classes before they were scheduled.