(NEW YORK) — A powerful typhoon is headed toward Guam, which could be the strongest tropical cyclone to impact the island in decades.

Super Typhoon Mawar could directly hit Guam with winds as strong as 160 mph — equivalent to a Category 5 hurricane. The strong tropical cyclone is expected to strike around noon local time Wednesday, which would be around 10 p.m. ET Tuesday.

A typhoon warning has been issued for the U.S. island territory, located in the western Pacific.

Rainfall could reach as high as 20 inches, and storm surge is forecast to reach as high as 25 feet. The super typhoon is already producing waves up to 45 feet in the ocean near Guam.

Guam’s Office of Civil Defense advised residents on Tuesday to seek shelter immediately, as Mawar is “expected to make a direct hit or very near passage for Guam.”

“There is a potential of a catastrophic and devastating event for Guam,” the office said in a bulletin.

Guam Gov. Lou Leon Guerrero also urged residents on Tuesday to seek shelter immediately as “damaging winds” were expected to start soon.

“Please take all the necessary precautions in an abundance of safety before we feel the full strength of the super typhoon,” she said on social media.

One emergency shelter in northern Guam had already reached capacity, the governor said.

President Joe Biden declared an emergency in Guam due to Mawar and ordered federal assistance to support the response to the typhoon.

A super typhoon is used to connote a tropical cyclone with sustained winds of at least 150 mph.

Mawar could be one of the strongest typhoons to impact Guam since the 1960s — the start of the satellite era.

The most destructive typhoon to hit Guam was Karen in 1962, with 155 mph winds and wind gusts of at least 170 mph, according to the National Oceanic and Atmospheric Administration. Most homes on the island were destroyed.

More recently, in 2002, Super Typhoon Pongsona moved near the island with 144 mph winds and gusts up to 173 mph, causing $700 million in damage at the time, according to NOAA.

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