Weak high pressure building up offshore spreads another day of partly sunny skies and 80-degree temperatures across Long Island, the National Weather Service said Monday.

Daily highs in the low 80s are expected for Nassau and Suffolk counties with a calm south wind from 5 to 9 mph.

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News 12 Long Island meteorologist Rich Hoffman said conditions for most of Monday should be "warm and humid."

Clouds increase later in the day and into Monday night, Hoffman said.

The nighttime hours still call for warm, humid conditions, he said, along with the chance for some scattered showers and thunderstorms into Tuesday morning.

Hoffman said there the threat of "some showers and storms" Tuesday and Wednesday.

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Overnight lows are in the 70s, giving way to clouds Tuesday, which is likely to be another warm, humid day with daily highs in the low to mid 80s.