Rain in Tuesday's forecast, along with possible coastal flooding

A storm system moving toward Long Island from the Ohio Valley is expected to deposit rain, included a chance of thunderstorms, starting Tuesday, the National Weather Service said.

The chance of rain for most of Nassau and Suffolk counties ranges from about 20 percent early Tuesday to up to 70 percent Tuesday night and into Wednesday morning, the service's Upton office said.

Much of the heavier rain from the system is expected north and west of New York City, the service said.

The rain system also is expected to generate some coastal flooding.

Rainfall amounts for Long Island could range from a quarter-inch to a half-inch on Tuesday to less than one-10th of an inch on Wednesday.

Daytime temperatures Tuesday and Wednesday are expected to be in the low to mid 70s with some of the storms producing gusty winds.

Clearing is expected by late morning Wednesday; there is a chance of showers and thunderstorms before 9 a.m.

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Wednesday night and most of Thursday are expected to feature clear skies and mild temperatures, the service said.

For most of the South Shore, from Brooklyn to southwestern Suffolk, a coastal flood advisory is in effect until midnight Tuesday.

For a large stretch of the North Shore, including the Bronx, Queens, Nassau and western Suffolk, a coastal flood statement is in effect until 2 a.m. Wednesday.

Both the flood advisory and flood statement mean "localized minor tidal flooding" during morning and evening times of high tide.

The advisory suggests larger tidal departures, from three-quarters of a foot to 11/2 feet; the statement means slightly smaller tidal departures, between a half-foot and one foot.

Roadways and property in low areas along the shore are particularly vulnerable to flooding, the service said.