Port Authority said this afternoon that riders should expect continuing delays during the evening rush hour.

And indeed, at 6:30 p.m., that prediction proved prophetic.

Riders on the T became stranded about 6:30 p.m. due to a system failure that affected the entire light rail system. Service was restored about a half-hour later, but trolleys were moving sporadically.

In a 4 p.m. statement, the authority said service is being provided on more than 100 bus routes and on the Light Rail Transit system. A complete list of routes, along with detours and service limitations, is posted at portauthority.org.

Sixty bus routes remain out of service due to weather-related issues across the county.

The T had been providing service to the First Avenue Station in Downtown. A power issue in the Downtown subway prevents service to the Steel Plaza and Wood Street stations. Bus shuttles had been serving temporary stops outside the stations.

The Mon Incline is operating. The Wabash Tunnel HOV lanes are closed. The authority is working to plow park-n-ride lots.

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