Southern Florida commuter rail carrier Tri-Rail says it will add 10 more trains for its week-day runs, beginning on Monday, March 27.

The additional trains will increase Tri-Rail's service by 33 percent before the annual summer surge in gas prices is expected to begin, the commuter train service said in a press statement on Friday.

With the additional service, some Tri-Rail trains will run as little as 20 to 30 minutes apart during rush hour, Tri-Rail officials said in the announcement.

Completion of all but two miles of double track made the increase possible, the announcement said.

More trains are expected to be operating on the weekends, too, with two-hour gaps between trains, down from as much as four hours during construction, Tri-Rail said. Weekend fares start at $2.

Monthly tickets, which allow passengers unlimited access to the trains, start at $40 for students, seniors 65 years or older, Medicare card holders and people with disabilities. Sixty-dollar packages are available for members of Tri-Rail's Employer Discount Program. Full-fare monthly tickets run $80 a month.

Tri-Rail service is offered in Palm Beach, Broward and Miami-Dade counties.