TTC riders should prepare for longer than normal wait times during the Friday morning commute.

The system experienced signal issues at its Wilson train yard this morning, preventing about a dozen trains from entering service on time.

Shortly after 8 a.m., around 50 trains were running on Line 1, as opposed to the usual 62 during peak periods.

The TTC says it won't likely have its full fleet up and running until after the morning rush.

"We are going to be short so we are advising people that there will be longer than normal wait times," said TTC spokesperson Brad Ross. "The morning rush hour is going to be a problem."

The transit agency says it may deploy shuttle buses from Bloor-Yonge Station to Union Station to alleviate the crowding.

Due to longer than normal wait times on Line 1, customers can use the downtown express routes (141, 142, 143, 144 & 145 routes) without paying an extra fare.<a href="https://twitter.com/hashtag/TTC?src=hash&ref_src=twsrc%5Etfw">#TTC</a> —@TTCnotices

The TTC has also initiated its so-called "GO-protocol" during the delay, which allows riders to use the GO system within Toronto for the price of a normal TTC fare.