Timeline: Icy Blast to Freeze Long Island Overnight
Temperatures on the East End will remain a bit higher than other areas of Long Island.
According to Joey Picca, meteorologist for the National Weather Service office in Upton, while temperatures across Long Island Monday at around noon ranged from the upper 40s across Nassau County to the lower 50s across the East End, a dramatic drop is expected as the day progresses.
At around 3 p.m., temperatures are expected to hover in the upper 40s.
Then, around 6 p.m. temps will drop to the mid-30s across all of Nassau County and western Suffolk, with slightly higher numbers, in the upper 30s, on the East End.
The East End will be the last area for temperatures to drop off as the cold air moves in from the west, Picca said.
Around 9 p.m., temperatures in the upper 20s are slated for Nassau County and western Suffolk, with readings in the low 30s on the East End.
During the overnight hours, closer to midnight, temperatures will drop to the lower 20s across most of the Island, except for the far East End, where temperatures in the upper 20s are anticipated.
Then, around, 3 a.m., an icy decline into the mid-teens is expected over most of Long Island, with readings of temperatures in the upper teens to the lower 20s on the East End.
The most dramatic drop will be reported heading closer to sunrise; around 6 a.m, temperatures will drop to the upper single digits across most of most of Nassau County and the western half of Suffolk, with temps in the lower to mid-teens on the East End.
On Tuesday, around 9 a.m., the morning commute will be cold, with single digits expected across all of Nassau County and western Suffolk, and highs of 15 degrees on the East End.
The cold snap, Picca said, is caused by a very strong cold front and a large area of cold high pressure pushing in from midwest into the northeast.
The headline-making frigid air that the midwest has seen during recent days will move, in a modified version, across the tristate area.
On the East End, some snow showers could be slated for the forecast on Tuesday, as cold air crossing over the Long Island Sound combines with the cold temps, Picca said.