Forecast: Much cooler weekend with below normal temps

A week into September and along comes a weekend with two days of temperatures that are actually a little and then a lot below normal for this time of year, forecasters say.

Saturday, which is looking at highs in the low to mid 70s, is also bringing slight chances of showers in the morning, followed by party sunny skies, the National Weather Service said.

South Shore beaches are looking at a high rip current risk Saturday from 8 a.m. to 8 p.m.

Sunday, featuring chances of showers starting in the afternoon, is expected to warm up only to the upper 60s — well below the normal high for the day, which is 76 degrees at Long Island MacArthur Airport.

This will be quite a switch for Long Islanders, who have seen day after day of hot, humid conditions. As of day-end Thursday, the temperature at the airport had averaged out to 7.4 degrees above normal so far this month.

Monday, then, is looking at the likelihood for rain through the day, with some thunderstorms, the weather service said. Temperatures that day head up to the mid 70s.

Though it was too early for the National Hurricane Center “to determine the exact location, magnitude, and timing” of any potential direct impacts to the East Coast next week from Tropical Storm Florence, the weather service’s Upton office said the Long Island area would likely see some effects through Thursday and possibly beyond.

“Swell arrives over the weekend, and increases through the week," the weather service said. And, look for high risk for rip currents, with potential for some beach erosion.