Long Island weather forecast: Fall to start with sunny skies

A cloudy Saturday should give way to a sunny first day of fall this Sunday, according to the National Weather Services’ forecast.

Suffolk residents can expect a high temperature in the mid-70s while temperatures may reach the high-70s in Nassau on Saturday, the weather service predicts. Mostly cloudy conditions are predicted all day Saturday, and temperatures are predicted to drop just under 60 degrees that evening.

Temperatures will reach the mid-70s across the island on Sunday, and the NWS predicts Long Islanders can expect a mostly sunny autumn day. In the evening, as temperatures again drop below 60, Nassau residents can anticipate some clouds while folks in Suffolk can expect clear conditions.

These temperatures are “near normal” for the change from summer to fall, said meteorologist John Christinello with the weather service’s Upton office.

Christinello said East End residents “can’t rule out” showers on Saturday, but the chances are around “30 or 40%.” He also predicts a dry Sunday for the whole island.

Despite the limited chances of precipitation, the weather service said multiple rounds of coastal flooding — which began Thursday evening — will continue this weekend.

The weather service issued a coastal flood warning for the southern parts of Queens and Nassau County between 10 a.m. to 3 p.m., which it said could bring 1 to 2 feet of inundation above ground level in “vulnerable” waterfront areas.

The weather service also issued a coastal flood advisory — which it said could bring up to 1 foot of shoreline inundation — in the northeast, southeast and southwest areas of Suffolk County on Saturday from 10 a.m. to 4 p.m. The service said residents of northwest Suffolk, as well as those in northern Nassau and the Bronx, can expect similar conditions during an advisory issued for Saturday between 11 a.m. and 4 p.m.

Christinello said he expects additional advisories are “coming for the rest of the weekend” to alert residents to the potential for “minor flooding.”

At this point, Cristantello added that “we are beyond” the impact of Tuesday evening’s full moon on high tides, but a northeast wind continues to pile up waves, leading to multiple rounds coastal flooding. He expects the wind “will become lighter and become more easterly” Monday or Tuesday, resulting in “lower chances” of coastal flooding.

The weather service also warned of dangerous rip currents along the South Shore in both Nassau and Suffolk through Saturday evening, with life-threatening rip currents likely for anyone entering the surf zone.