Vehicles navigate through flooding on Main Street, west of Griffing...

Vehicles navigate through flooding on Main Street, west of Griffing Avenue in Riverhead, on Monday as heavy rain and thunderstorms swept through the east end. Credit: James Carbone

The Long Island forecast calls for mostly cloudy skies and a decent chance of showers and thunderstorms through Wednesday night before sun and high heat return Thursday.

Predictions of unsettled weather follow a comfortable and mostly sunsplashed Long Island weekend when temperatures hovered in the mid-80s.

By Sunday afternoon, though, clouds began to roll in. The National Weather Service said a 50% chance of showers and thunderstorms was possible overnight into early Monday.

"Given the pattern we're in, we have chances of showers and thunderstorms through much of the week," said James Tomasini, a National Weather Service meteorologist with the Upton office Sunday.

After 2 p.m. Monday, according to the weather service, there's a 40% chance of both, with a high of 84 degrees.

The sun peeks through Tuesday on an otherwise cloudy day with a high of 84 and a 40% chance of rain, the weather service said. Wednesday is forecast to be mostly cloudy with a high near 85 and a 60% chance of rain. The overnight lows through Wednesday will dip to about 70.

About an inch of rain could fall before the system moves on, the weather service said. 

The Suffolk County Water Authority said in a statement Sunday that "due to a lack of precipitation in recent days, we are seeing water usage increase as more customers water their lawns and gardens. Water storage tanks are reaching low levels and you may be experiencing low water pressure in your home."

The authority urged residents to reduce water usage "to help restore reserve levels and ensure there is water availability in case of a fire emergency."

Long Island will warm up Thursday and Friday as temperatures approach the upper 80s with plenty of sun, but more rain possible overnight.

A trip to the emergency room in a Long Island hospital now averages nearly 4 hours, data shows. NewsdayTV's Virginia Huie reports. Credit: Newsday Staff

'I'm going to try to avoid it' A trip to the emergency room in a Long Island hospital now averages nearly 4 hours, data shows. NewsdayTV's Virginia Huie reports.

A trip to the emergency room in a Long Island hospital now averages nearly 4 hours, data shows. NewsdayTV's Virginia Huie reports. Credit: Newsday Staff

'I'm going to try to avoid it' A trip to the emergency room in a Long Island hospital now averages nearly 4 hours, data shows. NewsdayTV's Virginia Huie reports.

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