NJ Transit warned commuters Thursday of a catastrophic overcrowding of New Jersey's roadways if railworkers strike at March 13 — with more than 10,000 cars on the road per hour and overflowing buses leaving 65,000 mass transit commuters unserved.

"Don't even think of driving during the peak hours, and don't even think of driving solo," said Sam Schwartz, a former NYC transportation commissioner and consultant who is working with NJ Transit on its contingency plans. He warned major roadways approaching New York crossings —including the New Jersey Turnpike and Route 78 — could see backups of as much as 23 miles.

If 4,200 workers strike, there will be no rail service, and rail tickets will be cross-honored by private and NJ Transit buses. That's if you can fit onto a bus. Travel times will be severely impacted.

Authorities urged drivers to leave before 6 a.m. or after 10 a.m. for their morning commutes. Truckers were asking to avoid the Lincoln and Holland Tunnels. NJ Transit is asking employers to be flexible about work schedules.

The Hamilton to midtown New York City trip an NJ Transit train is currently 65 minutes, Schwartz said. The same trip via bus and then PATH train would take 2 hours and 15 minutes.

"Some people might be spending four to five hours commuting back and forth," Schwartz said. He said the scenario is "not a pretty picture, but we want people to be aware.

Morristown to midtown would go from just over an hour to just over two. Route 17 to midtown, now at 70 minutes, would be about an hour and 35 minutes.

According to NJ Transit, 105,000 rail riders would be displaced by the strike. About 40,000 could be accommodated via buses, Schwartz said.

He urged riders to begin getting to know their fellow rail passengers and begin making alternate plans for carpooling. And for those taking the buses: "Please be as patient and as friendly as you can, because these will be tough times."

NJ Transit will be providing updates throughout any stoppage — and the time leading up to it — at .

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