Updated at 1:48 p.m.

Metro said most of its bus routes had resumed service as of 1 p.m. Tuesday.

Many of its routes started operating at 7 a.m. Tuesday after being shutdown all day Monday in the winter storm. Some routes did not resume service earlier Tuesday because of roads that were still icy or hilly areas.

Three routes — the M8, the M9 and the U4 — will “remain suspended due to road conditions,” Metro said.

Ten routes in the region would also have to run on detoured routes because of the snow and icy road conditions, the agency said. Those routes included the A4, A6, A8, D12, P12, R12, S80, E6, 3A and 3T.

Original post at 7:11 a.m.

Metro said it resumed running buses Tuesday morning starting at 7 a.m. on all of its routes, but warned riders there could be detours in areas with hills, narrow side streets or other problem areas.

The transit agency had said Monday night that it would operate its bus service only on major roadways but early Tuesday morning changed that to buses would operate under a “moderate” snow service plan rather than a “severe” snow plan.

Metro’s rail service is expected to operate Tuesday under a normal schedule.

On Monday, Metro canceled its bus service for the entire day because of the snow and icy conditions.

VRE and MARC commuter rail services were running on a normal schedule Tuesday but officials warned there could be delays on the MARC “due to the continued extremely cold temperatures.”

Officials at transit agencies warned commuters to allow extra time and to use caution walking on sidewalks and platforms that could be slick from melting snow and ice that froze overnight. Riders were also reminded to dress warmly in case there were delays and they had to wait outside.

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