Insured losses from Typhoon Mangkhut in mainland China, Hong Kong and Macau have been estimated between $1 billion and $2 billion, according to AIR Worldwide.

After making landfall in the Philippines, Typhoon Mangkhut doused a relatively less densely populated agricultural area of Luzon with 12 inches of rain, although some regions received 27 inches of rain before the storm began to weaken, the Boston-based catastrophe risk modeling firm said in a statement Tuesday. By the time it had crossed Luzon into the South China Sea on Sept. 15, Mangkhut had weakened to a Category 3 storm.

The storm continued northwestward across the South China Sea the next day at wind speeds of about 100 miles per hour, Peter Sousounis, vice president and director of meteorology, AIR Worldwide in Boston, said in the statement.

“As it moved toward landfall in mainland China, Mangkhut bypassed Hong Kong and Macau,” he said. “The center of the typhoon passed 130 km west of Hong Kong and 70 km west of Macau, both of which felt its effects due to a massive wind field. Hurricane-force winds extended 160 km from its center and tropical storm force winds extended 510 km from its center. Storm surge was as high as 3.38 meters in Tai Po Kau, Hong Kong.”

Mangkhut maintained its wind speed and made landfall in Taishan, Guangdong Province, China, on Sept. 16 as a Category 3 hurricane, bringing heavy rain and strong wind to the province before weakening to a tropical storm and moving farther inland, AIR Worldwide noted.

 Record-breaking storm surges were recorded, and heavy precipitation brought waist-high flooding to some areas, inundating buildings, the firm noted. Glass windows on commercial skyscrapers in Hong Kong were shattered and contents were damaged.

In the resort city of Macau, all casinos were ordered to close for the first time ever. Power was cut to about 20,000 households in low-lying areas and the inner harbor. Extensive flooding impacted the area, rising above head height in some locations and damaging buildings and contents.

Along the coast of southern China, strong winds caused high-rises to sway and blew out windows. Heavy precipitation and storm surge flooded coastal hotels and businesses. Thousands of vehicles also suffered flood damage.

AIR’s modeled insured loss estimates include insured wind and precipitation-induced flood damage to property for mainland China, insured wind, storm surge and precipitation-induced flood damage to property for Hong Kong, insured wind and precipitation-induced flood damage to property for Macau and insured damage to automobiles for Hong Kong and Macau. AIR’s assumed takeup rates — the percentage of properties covered against wind and flood damage — were factored into the estimate.

According to its statement, AIR’s modeled insured loss estimates do not include losses to uninsured properties, losses in Guam, the Philippines or any other territory outside of mainland China, Hong Kong, and Macau, landslide or losses to land, losses to infrastructure or crops, livestock, aquaculture and poultry, losses resulting from physical failure of flood defenses and landslides or losses from storm surge in Macau and mainland China. It also does not include losses to automobiles and losses from business interruption in mainland China and losses from hazardous waste cleanup, vandalism, or civil commotion, whether directly or indirectly caused by the event, among other losses.