ARI SHAPIRO, HOST:
Hurricane Florence isn't the only big weather threat out there right now. In the Western Hemisphere, a storm named Mangkhut could affect more than 40 million people.
JEFF MASTERS: Right now, this is a super typhoon with 175-mile-per-hour winds, which ranks as a Category 5 storm on the U.S. scale.
SHAPIRO: Which means it's even stronger than Florence.
AUDIE CORNISH, HOST:
Jeff Masters, founder of Weather Underground, has been following Mangkhut on its path through the Pacific, where it's already been causing problems.
MASTERS: It crossed through the Northern Mariana Islands just north of the U.S. possession of Guam. And it brought Category 2 winds of about 105 miles per hour to the island of Rota, which is just north of Guam and caused some damage there but not catastrophic damage. Certainly, the storm's much more intense now and will cause greater impacts when it hits next time.
CORNISH: Its next target will likely be the Philippines, where officials have ordered evacuations.
MASTERS: It's expected to cross the northern part of the main island of the Philippines, Luzon, on Friday afternoon U.S. time. Then, it's going to enter the South China Sea and continue moving west and hit the coast of China very near Hong Kong on Sunday.
SHAPIRO: The second week of September is known as the peak week of hurricane season. Ocean waters are at their warmest, so it's pretty common to have intense storms in the Atlantic and Pacific at the same time.
CORNISH: But Jeff Masters says it is unusual to have several storms threatening U.S. states and territories simultaneously.
MASTERS: We've got a tropical storm hitting Hawaii today, Olivia, and in the Atlantic, of course, we've got Florence hitting the East Coast of the U.S. later this week. And also in the Caribbean, there is a storm that's going to threaten Puerto Rico, although it looks like it's going to potentially die out before it gets there later this week.
CORNISH: Jeff Masters, meteorologist and founder of Weather Underground. Transcript provided by NPR, Copyright NPR.