Hurricanes Close In on Hawaii


Hurricanes Madeline and Lester east of Hawaii on August 31, 2016. Image credit: NOAA/NASA

Hawaii is on the lookout this week for two hurricanes in the central Pacific Ocean that could each affect the island chain with dangerous wind, waves, and flooding. Hurricane Madeline is the closest and just a few hours away from its closest approach to the Big Island, which is home to Mauna Loa, Mauna Kea, and the city of Hilo. Hurricane Lester, a much more powerful storm than Madeline, is more than a thousand miles east of Hawaii and about four days from any potential impacts to the island chain.

The CPHC’s forecast track for Hurricane Madeline as of 5:00 AM HST on August 31, 2016. Image: CPHC

The early morning advisory for today, August 31, from the Central Pacific Hurricane Center said that Madeline had 80 mph winds as the Sun rose over the Pacific, and they forecasted the storm to continue weakening as it moves closer to land. A hurricane warning is in effect for the Big Island in anticipation of Madeline’s strong winds, flooding rains, and dangerous waves over the next couple of days. Several inches of rain across the island could produce flash flooding and mudslides. Much higher rainfall totals are possible on the windward side of the volcanoes where wind blowing up the higher terrain enhances lift and makes heavy rain even heavier.

The good news for Hawaii is that Hurricane Madeline has seen better days. The storm peaked on Monday with winds of 130 mph before beginning a steady weakening trend. Hawaii has had luck in recent years with tropical cyclones approaching from the east imploding in spectacular fashion before they hit heavily-populated areas either due to hostile winds, cold water, or the tall volcanoes shredding them apart. Madeline’s downfall is wind shear—strong winds disrupting the thunderstorms around the center of a storm are causing it to become disorganized and weaken. Wind shear is taking such a toll on the storm that its field of hurricane force winds extends only 10 miles from the center of the storm. Even for a small storm, that’s a remarkably tiny area of strong winds.

An animated infrared satellite loop of Hurricane Lester on August 31, 2016. Image: NOAA

Farther east, Hurricane Lester is raging through open waters strong as ever. Lester has maintained category four status for quite some time, peaking with winds of 140 mph on Tuesday before weakening slightly this morning. It’s a substantial hurricane on satellite imagery and has an ominous eye to match. The latest forecast from the National Hurricane Center brings Hurricane Lester perilously close to the Hawaiian Islands on Saturday and Sunday. Even though the current forecast shows the center of the storm missing just to the north, the state is solidly within the cone of uncertainty, or the historical margin of error in a hurricane track forecast. Even if Lester’s center goes north, the entire state will still feel the impacts of the system. Anyone who lives in or is visiting Hawaii this weekend needs to watch this hurricane closely.

Multiple hurricanes churning toward Hawaii isn’t as uncommon at is seems. The summer of 2015 saw three different category four hurricanes spinning in the central Pacific Ocean at once, the first time in recorded history we’ve ever observed so many powerful storms in that part of the world at the same time. Two of those storms tracked toward Hawaii, though they both missed the state to the north. Hurricanes Iselle and Julio also simultaneously approached Hawaii from the east in 2014—Iselle was the strongest storm to hit the Big Island in recorded history when it made landfall with 60 mph winds, and Julio behind it missed the island chain to the north. Powerful storms directly striking Hawaii are rare. The strongest storm to ever hit Hawaii was Hurricane Iniki in 1992; the storm devastated the island of Kauai when it made landfall with winds of 145 mph.