Philippine typhoon floods Manila, Quezon City landslide claims 8 - Chicago News and Weather | FOX 32 News

The southwest monsoon and moisture from Typhoon Haikui have worked together to bring flooding rainfall to Manila and other areas of the Philippines Tuesday.

At least eight people have died, as tens of thousands fled their homes, according to the BBC. The eight lives were claimed by a landslide in Quezon City. More people are still missing with rescues continuing.

Schools, businesses and the stock exchange have been shut as rain pours down.

Rainfall totals during a 48-hour period were as high as 20 inches across greater Manila as of Tuesday evening, local time. Even more rain may fall over the next few days.

The torrential rain is indirectly related to Typhoon Haikui. The distant tropical cyclone "enhanced" the rain-giving southwest monsoon over the Philippines. Haikui was centered over the East China Sea, southeast of Shanghai and more than 900 miles north of Manila, on Tuesday.

The southwest monsoon is enhanced when winds blow from the southwest across the China Sea. This draws moisture into China, Taiwan, and the Philippines. The moisture then interacts with the warm and humid air mass resulting in heavy thunderstorms and tropical downpours. The word "monsoon" means winds that reverse direction seasonally resulting in a period of heavy rainfall.

The mountains cause this air to rise even more causing the heaviest rains to fall in the higher elevations. Rainfall amounts in this 10-20" range causes significant stress on the soil resulting in massive mudslides and heavy runoff leaving to flooding.

There is another developing tropical cyclone in the area, but fortunately this storm will remain well north and east of the Philippines.