The holiday tradition is back.

Traffic is already backed up several miles on southbound Interstate 15 approaching Primm as the Memorial Day weekend concludes Monday.

Cars regularly line up on I-15 to leave Las Vegas and enter California on holiday weekends.

The interstate drops from three lanes to two when crossing the state line, creating congestion on busy travel days.

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California transportation officials have been working on adding a third lane on their side of I-15 for several months to alleviate the traffic.

If heading south into California, be sure to pack water and snacks for the wait and check your tire pressure before hitting the road.