Long Islanders were struggling with the aftermath of the historic weather event that had dumped double-digit amounts of rainfall Wednesday across parts of the area, flooding roadways, rail lines and basements.
The National Weather Service's Upton office said 13.27 inches came down on Islip between 11 p.m. Tuesday and 10:30 a.m. Wednesday, and another third of an inch fell Wednesday evening.
The Northeast Regional Climate Center said "rainfall of this magnitude is only expected to occur once in a 200-year period." The monthly rainfall for Islip is now 14.03 inches, which beats the record for August, set in 1990 at 13.78 inches.
The result was massive flooding in some residential neighborhoods and several major roadways in Nassau and Suffolk counties Wednesday morning, along with delays on Long Island Rail Road trains. There was at least one storm-related death in Melville, police said, and Suffolk officers had to swim to rescue a man Wednesday morning who had driven into 6-foot deep floodwaters on a Coram roadway.
As of Wednesday night, parts of Sunrise Highway, the Meadowbrook State Parkway, Ocean Parkway and the Robert Moses Causeway were still closed due to flooding.
But on the rails, the Long Island Rail Road was expected to operate a normal morning commute Thursday, with no planned cancellations or delays. A spokeswoman said some LIRR waiting rooms in Babylon branch train stations -- such as Seaford and Freeport -- took on water during the height of the storm.
The water has receded, she said, but there will be some restoration required in the stations that were inundated by water.
Late Wednesday, Gov. Andrew M. Cuomo said the Department of Financial Services' mobile command center would be in Islip to provide insurance assistance to homeowners, renters, and businesses affected by the flooding. It will be at the Islip Town Hall parking lot, 401 Main St., from 8 a.m. to 8 p.m. Thursday. The department's disaster hotline phone number is 800-339-1759.
The 13.57 inches was recorded at Long Island MacArthur Airport in Ronkonkoma and set a state record for precipitation in a 24-hour period, the weather service said.
According to a preliminary report, that amount breaks the previous mark of 11.6 inches recorded on Aug. 27-28, 2011, in Tannersville, during what the service referred to as Hurricane/Tropical Storm Irene.
Also reporting double-digit rainfall in Suffolk County locations were a weather service employee and trained spotters, with 12.57 inches recorded in Holbrook; 11.50 in West Islip; 11.35 in Bay Shore. Nassau saw 7.84 inches in Wantagh, 6.81 inches in Merrick, 5.30 in Lido Beach.
The one death that authorities said was weather-related was a fatal crash, on the westbound LIE in Melville, which occurred just before 5 a.m., during the height of the rainstorm.
The rain wreaked havoc on the Wednesday morning commute. Nearly every major roadway in both counties reported full to partial closures because of flooding as early as 4:30 a.m. Wednesday and until past noon, according to the state Department of Transportation.
Local roads were underwater as well. Suffolk County Sixth Precinct Police officers rescued an elderly man who became stranded in a flooded road in Coram Wednesday morning.
"Officers Thomas Wilson and Matthew Detleff were on northbound North Ocean Avenue conducting traffic control and diverting motorists due to extreme flooding, when a motorist apparently became disoriented" due to the road closure, a release said.
Anthony Monticciolo, 86, of Centereach, drove his 2008 Subaru into the flooded roadway "and his vehicle immediately became disabled" in waters 6 feet deep, which began seeping into his car.
The officers waded into the flooded roadway and swam to the victim's car, removing him and bringing him to safety, police said. He was uninjured, police said.
A PSEG Long Island spokesman said the utility considers the majority of Wednesday's outages to be weather-related. From midnight to 7:05 p.m. Wednesday there were 13,077 outages, and of those, 12,549 customers have had their power restored. As of 11 p.m., the remaining number of customers without power was down to 477.
The rains caused massive flooding in some residential neighborhoods.
Thomas Hall of Ocean Avenue in Massapequa woke up Wednesday morning to a flooded lawn.
"I opened the curtains and saw the backyard was like a lake," said Hall, 50, a retired correction officer.
He estimated the water had been about a foot and a half deep but a pump was working to drain off a low-lying portion of his yard Wednesday afternoon.
The storm flooded roads and basements in Rocky Point, Selden and Farmingville, and the lobby of Brookhaven Town Hall was closed for three hours because of flooding, Town Supervisor Edward P. Romaine said.
Romaine said he drove around town Wednesday morning observing "one flooding disaster after another" in northern and central sections of town. He estimated damage would be at least $1 million to $2 million.
The heavy rainfall also had an impact on water quality at local beaches, affecting bathing and shellfish harvesting.
Late Wednesday afternoon, the Suffolk County Health Department issued an advisory against bathing at 66 beaches until 7 p.m. Thursday as sampling is conducted because of the potential for elevated bacteria levels.
The Department of Environmental Conservation also closed shellfish harvesting in most towns in Nassau and Suffolk counties until officials determine hazardous conditions no longer exist.
With John Valenti, Gary Dymski, David M. Schwartz, Robert Brodsky, Mark Harrington, Ted Phillips and Carl MacGowan