If you’re headed for grandma’s on Thanksgiving Day you can expect decent driving conditions on Long Island, forecasters said.

Chilly morning temperatures give way to a slight chance of light rain after noon, the National Weather Service said.

Mostly it’s a cloudy Turkey Day with daily highs pushing toward 50 degrees.

News 12 Long Island meteorologist Rich Hoffman said there’s also a chance for some wet weather Friday and Saturday as people get out for weekend shopping.

“But most of the time it will be dry if you are heading out shopping or to get that perfect Christmas tree,” Hoffman said.

If you’re traveling by train anytime on the Thanksgiving weekend, the Long Island Rail Road is operating extra trains from Thursday through Sunday. The four-day period includes another boon: lower off-peak fares, even on Black Friday, when the regular weekday schedule resumes, the LIRR said.

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Over the four-day holiday, a special $1 fare applies for up to four children ages 5 to 11, as long as tickets are bought before boarding. As always, younger children ride for free.

Most travel experts advised those traveling to and from Long Island to allow for extra travel time.

In some areas north and west of New York City weather forecasters are calling for a light wintry mix.

Low gas prices and a strong economy could have about 2.7 million New Yorkers driving to Thanksgiving dinner, about 38,000 more than last year, and nearly as many as the record of 2.9 million set in 2005, according to AAA Northeast.

Drivers on state roads and bridges get a break, however; lanes that have been temporarily closed on state roads and bridges for construction instead will remain open from 6 a.m. on Wednesday until 6 a.m. on Monday, Cuomo said.