Bone-chilling cold expected on LI overnight

Brrrrrrr!

Real winter weather arrives on Long Island Tuesday, with snow flurries predicted for the late morning and early afternoon -- and a wind chill around zero on tap for overnight.

The National Weather Service says an arctic air mass will "usher in the coldest air mass of the season," with overnight temperatures falling into the teens and wind gusts of 25 mph or more dropping wind chills to near zero.

The frigid weather ahead is the result of a cold front from Canada that's passed through Michigan and the Great Lakes, forecasters said Monday.

"Behind that front is cold air," said Joe Pollina, a meteorologist with the weather service in Upton.

And until Thursday we can expect lower-than-normal temperatures for this time of year, Pollina said, adding that the front is expected to bring daytime temperatures in the low 30s and nighttime lows in the 20s through Wednesday.

Meteorologist John Murray said normal temperatures for this time of year usually hover just below 40 degrees.

"This is a very cold air mass," Murray said. "And it's going to be pretty much here Tuesday and Wednesday."

Tuesday night is expected to be especially cold, with a low of 15 degrees. The wind chills figure to make the weather outside feel like it's zero, he said -- maybe, even colder.

"It might feel a lot colder, especially at night, with the windchill factor," he said.

Flurries also could be in the forecast, Pollina said, but "if we get snow, there will be probably no real accumulation."

Temperatures will warm a bit starting Thursday, when sunny skies and a high of 43 degrees is forecast.

The weekend looks milder, with partly sunny skies and a high Saturday of 49 degrees.

Murray said the fluctuations are a product of changes in several factors, including the direction of the jet stream, but they are not unusual.

With Zachary R. Dowdy