HONOLULU (HawaiiNewsNow) -
When Iselle made landfall, the Big Island's big land mass cut into the wind swirling around the storm's center.
"As soon as it makes landfall you get this friction effect that causes the winds to blow into the eye and causes the eye to collapse and for the storm to weaken," University of Hawaii meteorologist Steven Businger said.
Some believe Mauna Loa and Mauna Kea took the air out of Iselle. Hurricanes and tropical storms do weaken when they pass over land. National Weather Service meteorologist Robert Ballard said that's what happened to Iselle, but it still packed a punch.
"There were damaging winds on Maui and Lanai. There was some damage on Oahu and Kauai even as the remnant circulation passed to the south," he said.
Businger said wind shear tilted Iselle to one side and took the top off the storm, but its trek upslope amped up the rain.
"We had up to 14 inches of rainfall in the typically wet places with the upslope flow as the storm arrived," he said.
Iselle is the latest proof that severe systems can hit the islands head on. The Big Island is a buffer for the rest of the state but not a barricade.
"It's really a very tiny shield for what we know are very hurricane prone islands," Ballard said.
"On Oahu, I think the winds and the rain was a lot less than it would have been if the Big Island hadn't been there," Businger said.
Iselle gives meteorologists lots to study. The data will help build models for future systems that set their sites on the 50th State.