Long Islanders should be dusting off their umbrellas for Tuesday, as rain is on its way. That would be 1 to 2 inches, with possibly as much as 4 in localized areas, forecasters say.

A "much-needed widespread rainfall event" is expected for Tuesday, said the National Weather Service forecast for the Island, which has been in a moderate drought since the third week in May.

With this part of August the peak time for summertime flash flooding events, forecasters will be watching closely for "a stripe of heavy rainfall" that could especially affect the New York City area, the National Weather Service said.

Rain is expected to start after midnight Tuesday, with heaviest rainfall expected during the morning commute. There's the potential for around three-quarters of an inch of rain to fall in some areas by around 8 a.m. Tuesday, said Faye Barthold, weather service meteorologist in Upton.

A flash flood watch has been issued for Nassau County from late Monday through Tuesday afternoon, warning of the possibility of 1 to 2 inches of rain -- higher in localized areas -- and a possible rainfall rate of up to 2 inches an hour.

Those localized heavy amounts could lead to "disruptive" conditions, said the weather service, pointing to flash flooding and its dangers.

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A potential for isolated flash flooding exists Islandwide, as well as "a small chance for a few strong to severe thunderstorms" Tuesday afternoon and evening, the weather service said in a hazardous weather outlook. Damaging wind gusts could present the main threat, the service said.

Tuesday also brings a high rip current risk at ocean beaches, the weather service said, in effect from morning through evening.

There's also a chance of showers and a thunderstorm into Wednesday morning, before it turns sunny later Wednesday.

"We really need rain and it looks like we could see 1 to 2 inches of rain," News 12 meteorologist Richard Hoffman said, pointing to a rainfall deficit of 7.38 inches since Jan. 1, and 3.01 since June 1. "A storm system will bring more humid weather and showers and thunderstorms for Tuesday. Some rain may be heavy at times and some flooding is possible."

It should remain sunny Thursday and into the weekend with the highest temperatures coming Friday, when it could be near 84, the weather service said.