Commuters on the Port Authority Transit Corporation train could be in for a headache this summer as an ongoing construction project is expected to shut down the south rail and cause 30-minute service interruptions.

PATCO train (Meredith Chambers, Townsquare Media NJ)

The closure, which is part of a $103 million PATCO rail rehabilitation project on the Ben Franklin Bridge, will run for 60 days starting May 30.

During that time, riders can expect schedule changes, delays, congested cars and service interruptions of up to 30 minutes as train cars will be "stacked" in Lindenwold for preparation of the morning commute, and in Philadelphia in the evening. Once the cars have all run, they will need to return in order to pick up remaining commuters during rush hour.

"We have the ability to move everyone during rush hour," said PATCO CEO John Hanson. "The trains are going to be crowded and there could be delays, especially if there is any failure with the circuitry. I would suggest that you allow extra time to get to your destination and look at the schedule so you don't get there at the beginning of these almost half-hour gaps."

Hanson said the biggest delays will be during rush hour and after concerts held in Camden's Susquehanna Bank Center.

"If you have any flexibility, it would be a good idea to take advantage of that and not travel during rush hour," Hanson said.

The first several trains leaving after a rush hour service gap are likely to be the most crowded, advised PATCO. The Transportation Authority also notes that reverse commuters might see empty cars being shuttled past them. The cars will be used during rush hour to transport the maximum number of commuters.

With the congested rail cars and delays expected to occur during the height of summer, many riders have complained about the potential heat and discomfort of being trapped in the cramped spaces.

"We are working on the air conditioning systems in the trains, we're replacing thermostats, we're cleaning the systems in some cases, we're replacing the HVAC motors," Hanson said.

He added that the authority is also working on ways to cool the platforms, as well as improve cellphone reception in the cars.

An additional closure will occur later in the summer and last for 50 days. In all, Hanson expects to lose 5 percent of PATCO commuters throughout the construction, but is confident they will return once service is fully restored.

"I am very sorry the commuters have to go through this," Hanson said. "We have no choice at this point. To keep those tracks safe and serviceable for a long time to come, we have to do this work now."