He warned that the end of the storm would only be the beginning of the cleanup.
“After the storm passes and skies clear, the work will not be over. Far from it,” Mr. McDonnell said. “Virginians in every region are going to be recovering from significant damage. Virginians are going to need help.”
Hoping to safely ride out the storm, federal workers learned at about 4 p.m. Monday that their offices were closed on Tuesday, along with the D.C. government and Maryland state government.
Early voting in the District and Maryland was also canceled for a second day.
Metro trains and buses were suspended through Tuesday morning, a spokesman said. Service would only be restored after as assessment of damage.
Amtrak’s Northeast rail service was halted for a second day.
All airlines at Dulles International Airport and Ronald Reagan Washington National Airport suspended service on Monday until further notice, and Baltimore-Washington International Airport warned travelers to expect widespread flight cancellations.
The threat of standing water and downed power lines prompted the second day off for schools in Prince George’s County and Montgomery County, as well as schools in Alexandria, Arlington, Fairfax and in the District.
The combination of high winds and saturated ground have officials worried, Mr. Schoor said, because the conditions are right for falling trees.
A half-dozen emergency shelters in Virginia and Maryland were opened on Monday in preparation for overnight damage caused by the high winds and heavy rain.
“Unfortunately, there are so many trees next to power lines,” Mr. Schoor said, and if they fall, they “can start to knock out power. This could happen here and across New England.”
• David Sherfinski, David Hill, Andrea Noble and Tom Howell Jr. contributed to this report.