Long Island forecast: A Memorial Day washout on the way

Don't bust out the grill just yet.

Memorial Day may be the unofficial beginning of summer, but cool, rainy weather is expected to dampen any barbecue plans on Long Island.

The National Weather Service forecasts a 90% chance of showers across the region Monday with temperatures near 70 degrees.

Thermometer readings have been "well below normal," said meteorologist John Murray, who works in the weather service's Upton office, adding that for this time of the year, the low 70s is the norm.

Rain on Monday could begin as early as 8 a.m. and continue until at least 2 p.m., dumping between a tenth and a quarter of an inch on the area, according to the weather service.

High surf and rip current advisories are in effect through Monday night for ocean-facing beaches on Long Island. 

"Anyone visiting the beaches should stay out of the surf," the weather service warns on its website. "Rip currents can sweep even the best swimmers away from shore into deeper water."

The National Weather Service warned on Sunday of "large breaking waves" up to 10 feet and "life-threatening rip currents" in the surf zone. 

The surf advisory, which covered Brooklyn, southern Queens, and the South Shore of Nassau and Suffolk counties, was in effect until 9 p.m. Sunday. Overall, however, it will be less-than ideal for anyone contemplating a Memorial Day at the beach.

"The water temperatures are still very, very cold," Murray said. 

The rough surf should ease Monday, Murray added, as gusts the weather service predicted could hit 28 mph Sunday die down. But swells could still reach 5 to 6 feet.

The high Sunday was forecast to top out just below 60, and the overnight low should dip to about 55.

Tuesday will be dry but mostly cloudy. The high is forecast to be about 75, dropping to 59 at night. Wednesday should bring a bit of sun, and a daytime high around 78.

Long Island is in a moderate drought, according to the U.S. Drought Monitor. Through Saturday, the Island had received 1.52 inches of rain so far this month, nearly an inch less than normal. Sunday’s rainfall will ease those conditions slightly.