Hawaii’s Mountains a Blessing as Tropical Systems Arrive

Hawaii is in the path of two powerful tropical cyclones, the generic name for the class of storms that includes hurricanes, typhoons and tropical storms.

This is the first time that has happened since at least 1949 and maybe longer, because no one alive has come up with another example. While conditions don’t look great for Hawaii, the island state does have a few things going for it.

Or at least might have.

The first is that Hawaii’s Big Island has some big mountains. Some of the volcanoes reach 13,677 feet (4,169 meters) and that’s enough to have an impact on Hurricane Iselle, which weakened to a tropical storm before reaching the island, as it moves west today.

While wind shear can topple a tropical system like a drunk stumbling into a wedding cake, mountains can have the effect of a toddler simply reaching a hand in the frosting to grab a piece with her fingers.

In the Atlantic, a hurricane crossing the island of Hispaniola -- home to Haiti and the Dominican Republic -- will get torn up, or as some meteorologists like to say: “shredded.” The question is, what is happening on the Big Island now?

Few hurricanes approach Hawaii from the east because the Pacific Ocean tends to be cooler on that side of the island chain. There isn’t a lot of information on what the volcanoes can do, said Paul Walker, a meteorologist with AccuWeather Inc. in State College, Pennsylvania.

The other thing in Hawaii’s favor today is that the second storm, Julio, is following in the footsteps of the first.

A tropical system churns up the ocean as it passes, and that can make the ocean’s surface cooler. Hurricanes, typhoons and tropical storms need warm water to build and maintain power.

There is a chance that if Julio crosses Iselle’s wake, it will lose a bit of power.

The best case would be for Julio to miss the islands altogether, which Walker said is a possibility.

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