Long Island weather: Scattered showers, possible flash flooding

It might just be a flash — but the sun could make an appearance Tuesday in between possible showers and thunderstorms, the National Weather Service said.

Look for isolated bouts of heavy rain Tuesday on Long Island, with the potential for flash flooding a continuing concern, forecasters say.

Thanks to a stream of moist, tropical air to the area, any showers that form Tuesday will have the potential to be downpours, as was the case Monday, said Carlie Buccola, a National Weather Service meteorologist in Upton.

Islip reported just under an inch of rain Monday, not counting anything that fell late in the day to overnight, according to the service. Meteorologists warned of possible minor coastal flooding with Monday night's high tide along Nassau's South Shore and back bays.

The month so far has brought only four days that have not delivered a trace or more of rain at Long Island MacArthur Airport in Ronkonkoma.

Temperatures were expected to rise to the low 80s Tuesday, which is just about normal at the airport for this time of year, meteorologists said.

Wednesday, forecasters expect conditions to turn drier and hotter, as mostly sunny skies are expected, with temperatures rising to the mid- to upper 80s, the weather service said. That’s followed by a similar forecast for Thursday, when humidity starts to build up.

August so far has been warm and wet, said Jessica Spaccio, a climatologist with the Northeast Regional Climate Center, based at Cornell University. That’s the result of a weather pattern that has developed across the northeastern United States, with a deep area of low pressure stalled to the west that has created a strong moisture flow from the Gulf Coast and south Atlantic northward into a narrow stream. That, Spaccio said, has led to “warm and humid air … being funneled up from the tropics.”

As of day's end Sunday, the monthly temperature was averaging 5.2 degrees above normal at the airport, she said, with precipitation surpassing the norm by 2.59 inches.

With Patricia Kitchen