Guam and the Northern Mariana Islands—both territories of the United States—are bracing for a punch from a strengthening typhoon in the western Pacific. The National Weather Service issued a sobering statement that “devastating damage is likely” as the typhoon passes very close to the islands on Friday.

Typhoon Dolphin isn’t a classically beautiful typhoon on satellite imagery, but what it lacks in appearances it more than makes up for in fury. The latest advisory from the National Weather Service in Guam shows that Dolphin has sustained winds of 110 MPH, and it should strengthen to category three status before it begins impacting the islands.

The forecast above shows Dolphin’s predicted path and wind field over the next couple of days as it moves through the region. The red shading indicates typhoon-strength winds (74+ MPH), with the worst winds and surge expected in the right-front quadrant of the eyewall, which would be just north of Rota if this forecast verifies.

Any leftward wobble in Dolphin’s forward motion from its forecast track would produce much more dire conditions in both Guam and Rota, which are home to a little more than 150,000 and 2,000 people, respectively. Forecasters at NWS Guam released a strongly-worded statement ahead of the typhoon, which is eerily reminiscent of the “Katrina Bulletin” issued by NWS New Orleans in the hours leading up to Hurricane Katrina’s landfall.

In addition to destructive winds and the potential for flash flooding, a three- to five-foot storm surge is possible in Guam during high tide. Most schools on Guam are closed in advance of the typhoon, and the government will open storm shelters for people to ride out the storm in a safe location.

The weather in Guam and Rota, like most tropical locations around the world, is remarkably stable, with constant temperatures and humidity levels throughout the year. Temperatures dipping five degrees below normal is a big deal—the average low in Guam’s capital of Hagåtña, is about 76°F, and the lowest temperature ever recorded in the city is 65°F. The only real variations in weather they have to worry about are tropical cyclones like Dolphin.

Tropical storms and typhoons can threaten Guam all year, but because of its small size, it rarely ever takes a direct hit from the eye of a storm. The last storm to make a direct landfall on Guam was Typhoon Pongsona in December 2002, which produced sustained winds of 145 MPH with higher gusts. The damage left behind in the hardest-hit areas was like what one would find in an EF-3 tornado.

Dolphin will continue to strengthen once it passes through the U.S. territories, and the National Weather Service expects it to grow into a powerful category four with winds approaching 140 MPH as it recurves to the north and then northeast, mostly out into open waters.

[Images: NOAA, NWS Guam]

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