The typhoon, named Ompong in the Philippines, will bring heavy rains and storm surges on its trail. The U.S. military's Joint Typhoon Warning Center forecasts top winds of 135 knots (155 miles per hour) with maximum gusts of 165 knots in the next three days.
Hong Kong had been bracing for a direct hit on September 12, but the typhoon warning was cancelled the morning of September 13, the Hong Kong Observatory announced, as forecasts tracked Mangkhut's path further south.
MANILA-Moderate to heavy rains are expected in most parts of the country starting Wednesday (Sept. 12) as the strong typhoon with global name "Mangkhut" continues to gain strength and moves westward into the Philippine Area of Responsibility (PAR). Moreover, Mangkhut will be the first storm to become a Typhoon of Category 5.
A super typhoon roared toward the Philippines on Thursday, prompting thousands to evacuate ahead of its heavy rains and fierce winds that are set to strike at the weekend before moving on to China.
Office of Civil Defence chief Ricardo Jalad said more than 4 million people in the northeastern provinces of Cagayan and Isabela and outlying provincial regions are vulnerable to the most destructive effects near the typhoon's 125-kilometre (77-mile) -wide eye.
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The typhoon is approaching at the start of the rice and corn harvesting season in Cagayan, a major agricultural producer, and farmers were scrambling to save what they could of their crops, Mamba said.
The typhoon is expected to boost the intensity of seasonal monsoon rains that have already caused widespread flooding in central Luzon, a mainly farming region north of capital Manila. The threat to agriculture comes as the Philippines tries to cope with rice shortages. In 2013, Super Typhoon Haiyan killed more than 6,300 people in the Philippines.
The Philippines is hit by about 20 typhoons and storms a year.
Medical and emergency response teams were on stand by, heavy equipment mobilised and more than 1.7 billion pesos ($31.45 million) of relief goods prepared as Mangkhut, known locally as Ompong, edged towards the storm-prone nation on its way towards southern China and northern Vietnam.