The Houston Independent School District said school campuses across the city will remain closed Friday due to "widespread damage." Whitmire urged all non-essential workers to stay at home Friday and said most businesses in downtown Houston will remain closed. The mayor added it could take up to 48 hours for power to be restored across the city. CenterPoint Energy, the city's main power provider, did not provide a timeline for restoring electricity but urged people to be prepared for "extended weather-related power outages and possible delays in some outage notifications."