LI weather: Summerlike weather Saturday before chill returns Sunday

Long Island will have summerlike weather on Saturday as temperatures are forecast to get into the low 80s throughout much of the area, but the National Weather Service is warning against swimming in the ocean despite the warm temperatures.

Weather service meteorologist Matt Wunsch called it a “one-day, temporary warm-up” to about 80 degrees on the Island caused by “the warm front of the very large system that moved through the area last night.”

“There’s a lot of warm air sitting over the area,” he said on Saturday morning. “Once the sun comes up, and we kind of start to mix down that warmth that’s sitting right above us, temperatures should rise pretty quickly.”

Wunsch said the warm temperatures will hit Nassau County and the western portion of Suffolk, but it will remain in the 50s and 60s on the Twin Forks.

Residents should still avoid swimming in the ocean on Saturday, however. The weather service issued a warning that said the water would remain cold and “can quickly cause hypothermia and physical incapacitation to anyone suddenly immersed in the water.”

“Keep in mind that even though the air temperature is warm, the water is still cold,” Wunsch told Newsday, explaining the weather service typically issues those warnings when there’s an unseasonably warm day in March and April.

Saturday’s warm weather will be short-lived. Rain is expected on Saturday night as temperatures drop into the high 30s, while Sunday is expected to be chilly and foggy.

“As we move into tonight and tomorrow, the front that pushed north last night, which is giving us the warmth today, pushes back south,” Wunsch said. “Temperatures are going to cool off pretty substantially tomorrow. Highs are only going to be in the upper 40s to low 50s.”

There’s a high chance of rain from Sunday night through Monday night, when the temperatures are expected to range from the low 40s to low 60s.

The weather will clear up on Tuesday when temperatures are expected to be in the 50s.

“Before we get to Tuesday we’ll have a front come through — showers, maybe some thunderstorms,” Wunsch said. “That should be ending by Tuesday morning. Then Tuesday will be mostly dry with highs from the low to mid 50s.”