A utility worker clears a downed tree in Springfield. (Cliff Owen/Associated Press)

Tens of thousands are still without power following the thunderstorm that streaked through the region, and schools and businesses are announcing closures.

Workers in the Washington area may take unscheduled days off or unscheduled telework days on Monday, OPM said in a statement.

Non-emergency employees must notify their supervisors of their intent to use unscheduled leave or unscheduled telework. OPM said eligible employees may:

· Use annual leave, earned compensatory time off, earned credit hours, or leave without pay; or

· As permitted by their agency’s policies, procedures and collective-bargaining agreements, telework from home on a non-telework day, if the employee has a telework agreement in place that is approved for unscheduled telework.