The system's wind gusts and lightning wreaked havoc on some parts of the Island, sending at least two people to hospitals and sparking fires as the thunderstorm downed power lines, trees and even a beloved gazebo.
More than 22,000 customers were without power at 7 p.m., up from about 14,000 customers just after 5:30 p.m., according to the Long Island Power Authority's website. By 11 p.m., power had been restored to all but about 7,600 customers, LIPA said.
The eastward-moving thunderstorm hit Long Island just before 1 p.m., touching down on Nassau's North Shore. Widespread thundershowers, some severe with large hail and winds in excess of 60 mph, had been forecast for the area between 2 and 4 p.m., the statement said, with flash flooding also a possibility.
Soon after the storm reached the Island, a wind gust blew down a 1932 gazebo at Morgan Memorial Park in Glen Cove.
Three fishermen had taken shelter under the open-air gazebo when the roof caved in about 1:20 p.m., injuring one of them, said Darcy Belyea, Glen Cove parks and recreation director. The victim was taken to North Shore University Hospital in Manhasset, she said.
Emergency operations were activated at about 2 p.m., with public works and emergency personnel called in to monitor the storm and clear debris from roads, Mangano said.
A conference call with North Shore village mayors had been planned for 5:45 p.m. to gather information on damage and needs, Mangano said.
"The storm hasn't reached the level of widespread damage yet," Mangano said about 5:15 p.m., as he was on his way to assess the damage in Glen Cove. "Right now, the damage we have is fallen trees, concentrated on the North Shore, but the storm is moving through the Island right now, so we expect other instances."
Fire departments in both counties were busy with storm-related problems, including several lighting strikes to buildings in Suffolk, police said.
Some flights at area airports were experiencing weather-related delays, according to the Federal Aviation Administration. Departures at Kennedy Airport were delayed about two hours, according to the FAA, while arrivals LaGuardia Airport were up to 45 minutes late and with the delays increasing.
Travelers are advised to check with their airlines for flight updates. The severe thunderstorm watch comes on a day when a heat advisory was in effect for Nassau and western Suffolk from 10 a.m. to 6 p.m., officials said.
It's also officially the third day of a heat wave, as the temperature at MacArthur Airport in Ronkonkoma hit 90 degrees as of 10:32 a.m., rising to 94 by 11:37 a.m. The mercury had hit 90 degrees at the airport on Monday, Tuesday and Wednesday.
A heat advisory is issued when the combination of heat and humidity is expected to make it feel like it's at least 100 degrees for two consecutive hours, the weather service said. Forecasters said the "immediate South Shore" could be spared.
A heat advisory also signals potential health hazards for seniors and for those suffering chronic health problems.
Still the "sultry" weather is about to break as the storms move through the area Wednesday, with Thursday expected to see lingering clouds in the morning and temperatures lower by about 10 degrees, says Tim Morrin, meteorologist with the weather service in Upton.
As for Friday, forecasters are now looking at the possibility of "light but long-duration rainfall," with temperatures in the 70s, Morrin said.
With John Valenti