Two storms are happening simultaneously at two ends of the world — Hurricane Florence over the U.S. east coast and Typhoon Mangkhut in the Phillipines. Here is how the two storms compare, the damage expected from each of them, and the difference between a hurricane and a typhoon.
A tale of two storms
Hurricane Florence is making landfall on the U.S.’s east coast near the Carolinas as a Category 1 hurricane with winds howling at 144 km/h. Rainfall of up to 101 centimetres is expected, likely triggering flash floods and landslides.
Meanwhile, Super Typhoon Mangkhut is nearing the Philippines at a threat level that is equivalent to a Category 5 hurricane, the highest category possible. The typhoon has sustained winds up to 267 km/h, with stronger gusts at 323 km/h.
Thousands of people have begun to evacuate northern Philippines on Thursday ahead of the projected landfall of Mangkhut on Saturday in Luzon, the largest and most populous island in the Philippines. Currently, 10 million people lie in the path of typhoon Mangkhut.
WATCH: Philippines braces for typhoon Mangkhut
Given Mangkhut’s higher categorization, it is expected to have a bigger storm surge, but Florence is expected to move slowly and linger much like Hurricane Harvey last year, exacerbating its effects. Mangkhut is expected to bring less rainfall than Florence because it is forecasted not to linger as long.
“Water is going to be the big issue with Florence whereas wind is the big issue with the typhoon,” said Bob Robichaud, a Warning Preparedness Meteorologist for Environment and Climate Change Canada.
Robichaud explained that water is usually a greater threat than wind for tropical cyclones. “We always tell people ‘run from the water, hide from the wind,'” he said.
WATCH: Hurricane Florence — scary scenes as powerful storm makes landfall overnight
One reason for this is because the threat of the super typhoon’s winds only exists where the storm makes landfall, whereas flooding can cover a vast area, and has historically killed more people than the wind of a storm.
However, although water often poses a greater threat than wind, it may not be the case between Florence and Mangkhut given the Philippines’ weaker structures compared to east coast U.S.
Mangkhut is currently on track to be as strong as Super Typhoon Haiyan that hit the Philippines in 2013 and killed more than 6,000 people.
Difference between typhoons and hurricanes
The difference between a hurricane and typhoon simply comes down to location. They are both tropical cyclones, meaning low-pressure circular storm systems with winds great than 120 km/h that form over water, but the different terms are used in different parts of the world.
In the western North Atlantic, central and eastern North Pacific, Carribbean Sea and Gulf of Mexico, such tropical cyclones are called hurricanes, whereas in the western North Pacific, they are called typhoons.
A storm can even start as a typhoon and become a hurricane, or vice versa, if it crosses the international date line that serves as the Pacific Ocean’s dividing marker.
Hurricanes and typhoons typically develop in different times of the year. This year’s Atlantic hurricane season runs from June 1 to Nov. 30, whereas typhoons typically form from May to October, although they can form year-round.
Whereas hurricanes are defined by a five category system, typhoons are classified as “typhoon,” “very strong typhoon,” or “violent typhoon” by the Japan Meteorological Agency.
The Joint Typhoon Warning Centre, a U.S. military command in Pearl Harbour, Hawaii, also designates typhoons as either a “tropical depression,” “tropical storm,” “typhoon” and “super typhoon.” Typhoon Mangkhut is a super typhoon.