The National Weather Service is advising drivers to use "extreme caution" and to beware of black ice as temperatures drop below freezing overnight.
Black ice is clear, difficult to see and extremely slick. Weather service meteorologist Brandon Smith said snow that melted near and on roads during the day will freeze overnight and some will become black ice.
A similar pattern - of daytime snow melt followed by freezing and ice formation on roads at night - could be in place for the next several days, Smith said.
The weather service is predicting temperatures on Long Island to reach the low 20s overnight and to rise just above freezing Tuesday.
"Slow down," Smith said. "Leave extra room between you and the car in front of you. Be aware that the road conditions could change rapidly."
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