Service was suspended on the Ronkonkoma Branch in both directions between Farmingdale and Ronkonkoma because of a broken rail east of Brentwood. Trains were running again by 11 a.m. on Friday, but not before buses had to carry commuters throughout the morning.
The freezing temperatures have caused at least seven other tracks to break this week.
A broken rail east of Mineola delayed Thursday night's commute.
Passengers had to wait as crews rushed to replace the rail.
The LIRR says a delay is better than a derailment.
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