The White House has shut down – the “Winter White House,” that is.

President Trump’s oceanfront Mar-a-Largo estate in ritzy Palm Beach has been closed because of Hurricane Irma, the Trump organization said Friday.

The president’s other Florida properties – including the Trump International Golf Club in West Palm Beach and the Trump National Golf Club in Jupiter – have been closed as well in response to the expected monster hurricane.

The organization urged people staying at the hotel Trump National Doral to find alternative lodging that is not in the storm’s path.

"We are no longer accepting any new reservations at this time and in the event that the city of Doral is included in any evacuation order, affected guests will be required to find alternate lodging outside of the evacuation zone or possibly relocate to an evacuation center," the statement said.

"We continue to send our thoughts and prayers to victims of Hurricane Harvey and are praying for those that are in the path of Hurricane Irma," the statement said.

Strikes by four major hurricanes have done little damage to Mar-a-Lago in the 90 years since cereal heiress Marjorie Merriweather Post and her second husband, financier E.F. Hutton, built the 126-room, 62,500-square foot mansion. It cost them $5 million — the equivalent of almost $70 million today.

The three-acre estate is exposed to tropical weather, bisecting a narrow barrier island, flanked by the Intracoastal Waterway and the Atlantic Ocean. But the mansion's walls are three-feet thick, anchored by steel and concrete beams embedded into coral rock.

"It's the safest place in the world for a hurricane," said Anthony Senecal, Trump's longtime butler and Mar-a-Lago's unofficial historian, in an interview with The Associated Press last year. "That house ain't going nowhere. That house has never been seriously damaged. That construction, stop and think about it. There were 300 guys that worked on the outside of that building."

On Friday, shutters could be seen covering some of the mansion's windows.

Jeff Masters, director of the Weather Underground forecasting service, said Thursday that the biggest threat to Mar-a-Lago won't be Irma's winds, which could top 140 mph when it reaches Palm Beach. Instead, it will be storm surge, which he said could reach eight feet in a worst-case scenario. An interactive map by Climate Central shows that a more likely six-foot sea rise would put some of the property's low-lying areas at peril. An eight-foot surge could cause some water damage to the main buildings.

Trump bought the property in 1985, when it was in disrepair, for $10 million, and spent millions refurbishing it before turning it into a club in 1995. The property now boasts 58 bedrooms, 33 bathrooms, a 20,000-square-foot ballroom, tennis and croquet courts and three bomb shelters.

The Trump family business doubled the initiation fee to $200,000 once it became clear that Mar-a-Lago would become the unofficial Winter White House, and the president has spent seven weekends at the resort since his inauguration, mingling with the club's 500 members, who pay $14,000 in annual dues to belong.

The Associated Press contributed to this report.