Hagupit, known locally as Ruby, was downgraded from a super typhoon and expected to weaken slightly but to remain a top-level Category 5 storm with life-threatening winds, storm surges and flash floods.
"This storm is not going to be quite as strong as Haiyan, but the probability is it has the potential to impact some of the same areas that were impacted last year," said Ari Sarsalari, a meteorologist for The Weather Channel. Haiyan killed more than 7,000 people in the Philippines in November 2013 and left more than 4 million homeless.
"This is definitely the type of situation that can get very ugly," Sarsalari added.
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Some weather agencies had suggested earlier that Hagupit could take a northerly route skirting the country. But by 5 a.m. Friday (4 p.m. Thursday ET), the Philippine and Japanese national weather bureaus and the U.S. Navy's Joint Typhoon Warning Center all said its course had clarified and agreed that it was most likely to remain on course for the Philippines.
Hagupit's slow movement is expected to cause significant problems. The Philippine weather bureau said it could be as late as Wednesday before the storm clears the islands, leading to rainfall totals Sarsalari called "extraordinarily high," causing landslides, debris flows and life-threatening flash floods.
At least 15,761 families in Tacloban City in Leyte province — where 3,000 people were killed by Haiyan last year — were being evacuated on Thursday, local officials told the Philippine Daily Inquirer, the country's largest newspaper.
Col. Restituto Padilla, a spokesman for the Philippine military, said at a briefing that the armed forces were on "red alert" and were rushing troops and equipment into position. He said the military was intent on making sure that "the disaster-prone areas are safe."