Temperatures could reach 10 degrees above average Tuesday into Wednesday on Long Island, forecasters said.

The National Weather Service has issued a Severe Thunderstorm Watch through Wednesday evening for all of Long Island, New York City and points west.

The thunderstorm watch is in effect as strong isolated thunderstorms and a more organized system moves into the region from Pennsylvania, then goes west to east over the area, the weather service said.  The watch lasts until midnight but there could still be more storm activity through the overnight hours, the weather service said.

Long Island could begin to see the storms about 9 p.m., the weather service said. Forecasters said, in the heaviest activity, the storms have the potential to bring up to two inches of rain per hour and gusts up to 65 mph and even a slight chance of hail. 

No major flooding is predicted, but brief flash flooding is possible in low-lying areas or flood-prone areas with poor drainage. Some isolated tornadoes are also possible in the warning area, which includes parts of the Hudson Valley, New Jersey and Southern Connecticut. 

“The storms are moving through Pennsylvania and over the metro area and into Nassau County,” said National Weather Service Meteorologist Dominic Ramunni said. “There should be scattered showers and storms over Long Island, which may continue into early overnight until 4 a.m.”

Thunderstorms are the result of a cold front meeting the hot, humid air that has been lingering over Long Island this week. The cooler air mass then lifts up and can make the loud summer thunderstorms, Ramunni said. 

Showers could last until Thursday morning before temperatures rise again into the mid-80s and skies clear. Temperatures are predicted to cool off by Friday, with highs expected in the 70s to low 80s, according to the weather service.

Another chance of thunderstorms and showers is predicted for Saturday night and Sunday.

A high rip current statement is also in effect until 9 p.m. Wednesday for all southern Long Island beaches from Suffolk County to Coney Island.

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