Long Island weather forecast: Heavy rains could bring flooding

Flooding caused by heavy rains and thunderstorms is possible Monday evening across much of Long Island, and the chance of showers and more storms will persist through Tuesday.

Shortly after 5 p.m. Monday, the National Weather Service issued a flood advisory for Nassau and Suffolk counties through 7:15 p.m. About 6:25 p.m., meteorologist James Connolly said around one to two inches had already fallen in Nassau and western Suffolk, but the weather service had not yet received any reports of flooding or storm damage in either county.

By Tuesday evening, the total amount of rainfall could reach three inches, with higher amounts possible in some areas, Connolly said.

"It's going to depend on where the heavier showers and thunderstorms set up," the meteorologist added.

The excessive rainfall in such a brief period on Monday could spell "minor flooding in low-lying and poor drainage areas" including Garden City, Plainview and Westbury in Nassau and Dix Hills, Huntington, and Northport in Suffolk, the weather service said in the advisory. 

Regarding driving through flood areas, the weather service said: "Turn around, don`t drown when encountering flooded roads. Most flood deaths occur in vehicles."

Meteorologist Brian Ciemnecki said the chance of rain would gradually increase during the afternoon and evening and Long Island will see moderate to local heavy showers at times.

"There could be some thunder along with it," Ciemnecki said.

Temperatures reached the mid-to-upper-70s on Monday, although meteorologist Brian Ciemnecki told Newsday those mild highs "may feel muggy with all the moisture in the air."

The weather service warned of a high risk of "life-threatening" rip currents at New York City, Nassau, and western Suffolk beaches Monday for anyone entering the surf zone. 

Rainfall will continue into Tuesday morning, with highs in the upper 70s.

Wednesday and Thursday may be this week's ideal days for outdoor activities, as they will offer a reprieve from rain, with mostly dry conditions.

Temperatures will also increase, with highs in the upper 70s and lower 80s.

A chance of showers will return Friday into Saturday. Conditions should clear for a dry and warm Sunday.