"Road conditions are expected to deteriorate later this afternoon, and it is essential to get federal workers home before dark so transportation authorities can treat the roads," OPM's Web site stated.
Emergency employees were expected to remain at work.
The National Weather Service placed the area under a winter storm warning until Wednesday afternoon as snow and freezing rain hit. Accumulations of 3 inches to 5 inches are possible, according to the agency's Web site.
OPM's announcement applies to employees, including those who telecommute, who work in executive branch agencies located inside the Capital Beltway. It does not apply to postal workers or federal contractors.
Agencies outside the Beltway and in other cities across the country announce their operating status individually.
Federal employees should monitor local media outlets or the OPM Web site for updates on the storm and the government's operating status.