Hong Kong, southern China brace for powerful Typhoon Ragasa after it batters the Philippines

Tyrone Siu/Reuters via CNN Newsource

By Helen Regan, Taylor Ward

(CNN) — A huge and powerful typhoon is headed toward southern China after lashing the Philippines with destructive winds and torrential rain, putting the region’s megacities on high alert with cancelled flights and disruptions to schools and businesses.

Tens of millions of people could be impacted by the storm, which is expected to pass south of the major cities of Hong Kong, Macau, Shenzhen and Guangzhou, before making landfall again in mainland China’s Guangdong Province.

Typhoon Ragasa hit the northern Philippines as the strongest storm on earth so far this year, after generating sustained winds of over 165 mph (267 kph) , the equivalent of a Category 5 hurricane.

The sheer size of the system churning its way th