Updated at 10:11 a.m.

Metro commuters experienced multiple delays during the morning rush on Friday, as the transit agency reported seven disabled or malfunctioning trains on the Red, Orange, Blue and Green lines. A spokesman for the agency said the snowy and extremely cold weather may have contributed to the problems.

Most of the delays were resolved in a relatively short time, ranging from 10 to 30 minutes. Officials said that the snowy weather and cold temperatures meant more workers stayed home and the trains were less crowded than usual.

“We have seen an uptick in mechanical issues, and it would not be inconceivable that weather is playing a factor,” Metro spokesman Dan Stessel wrote in an email. He said ridership is light “and there are no significant crowding issues.”

In a follow-up e-mail, Stessel said the delays have been “the result of mechanical issues with the rail cars themselves. No track/signal/switch issues thus far.”

From 6 a.m. until 9:30 a.m., Metro’s alert system on Twitter and by email kept firing warnings at riders to expect delays.

Several of Metro’s bus routes had troubles as side streets were not plowed, downed power lines blocked roads and minor accidents tied up traffic.

At 9:30 a.m., delays continued in both directions on the busy Red Line after an earlier issue that involved a disabled train at Bethesda. Trains had to share a track to get around the problem.

Riders reported delays on Twitter.

— dcmetrosucks (@dcmetrosucks) January 3, 2014

At 9:01 a.m, Metro said normal service had resumed on the Blue and Orange lines after a problem at the Rosslyn station. By 9:15, Metro said normal service was back on its Green Line after an earlier incident at the U  Street/Cardozo stop.

At 10:08 a.m., Metro said normal service had resumed on its Blue and Orange lines at the Federal Triangle stop.

Updated at 8:51 a.m.

Metro said trains are no longer sharing a track between Friendship Heights and Medical Center stops. But delays continue in both directions.

The earlier problem was a disabled train at the Bethesda stop.

Metro has had six hiccups in a span of three hours on its rail lines.

Officials did not immediately return calls to answer any detailed questions of what caused the problems.

Updated at 8:46 a.m.

And another delay on Metro Friday morning.

Riders should expect delays to Branch Avenue on the Green Line because of a disabled train at the U Street stop.

Updated at 8:24 a.m.

A disabled train at the Bethesda Metro station is causing delays on the Red Line, the third problem on the busy rail line this morning.

Trains are sharing a single track between Friendship Heights and Medical Center stops.

Updated at 8:08 a.m.

The Red Line is back to normal operations, according to Metro.

Original post at 8:00 a.m.

Metro riders on the busy Red Line should expect delays Friday morning in the direction of Shady Grove stop.

The incident is due to an earlier train malfunction at Judiciary Square.

There were earlier delays on Metro’s Red, Orange and Blue lines Friday morning, but they were resolved.