Heather Geraci, 3, of Southold, and her nana Katie Geraci at...

Heather Geraci, 3, of Southold, and her nana Katie Geraci at the Reichert Family Community Playground in Peconic on Tuesday. Credit: Randee Daddona

Long Islanders should keep their jackets and umbrellas handy, as a nearly 20 degree temperature plunge is forecast midweek, ditto for showers that could dampen Memorial Day weekend, according to the National Weather Service.

Wednesday will be the last in a series of days marked by high temperatures that have soared into the 80s. Normal temperatures for this time of year are around 70 degrees, weather service meteorologist Joe Pollina told Newsday in a Tuesday afternoon phone interview.

A chance of showers and  thunderstorms are forecast for Wednesday evening when a cold front brings "the chillier weather" to Long Island, Pollina said. These storms "could be severe, with damaging winds the main threat," a weather service alert issued Tuesday said. Along with thunderstorms, a heat advisory with temperatures in the 90s is in effect for the  metropolitan area on Wednesday.

Showers also could occur on Thursday, when highs will reach only to the mid-60s. Friday will remain sunny and dry during the day, with temperatures just as mild, but evening showers are likely.

Rain could befall those enjoying any day of their three-day weekend, but "part of the weekend might be salvageable," Pollina said.

"There’s a chance of rain through the weekend, but it looks like it’s not going to be a washout," the meteorologist added. "Saturday morning, we’re looking at a 70% to 80% chance of showers ... Sunday, we’re looking at a 30% to 50% chance across the island. Then by Monday, we’re looking at only a 20%, 25% chance, so a slight chance, of showers."

Temperatures will rise early next week, but only to normal or slightly above normal temperatures, according to Pollina. Forecasters are not predicting more 80 degree days for the near future.

Get the latest news and more great videos at NewsdayTV Credit: Newsday

Full LIRR service restored. ... Honoring their service by cleaning their headstones ... LI Works: Hampton Ice ... When will the heat end? ... Get the latest news and more great videos at NewsdayTV

Get the latest news and more great videos at NewsdayTV Credit: Newsday

Full LIRR service restored. ... Honoring their service by cleaning their headstones ... LI Works: Hampton Ice ... When will the heat end? ... Get the latest news and more great videos at NewsdayTV

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