Hawaii Braces

Tropical Storm Flossie is almost out of steam, but by tonight, looks to make a direct landfall somewhere on Maui, Oahu, or Kauai. Tropical storm warnings and flood warnings have been issued by the National Weather Service in Honolulu. The storm formed over the open waters of the Eastern Pacific on July 25, and never reached hurricane strength.

Thanks to wind shear and plenty of dry air in the region, Flossie has been weakening on its final approach to the islands, but still will be a threat for tropical storm force winds (sustained near 40 mph, with higher gusts), and torrential rainfall. Though the center of circulation should pass directly over one of the smaller islands, most of the remaining thunderstorm convection is hanging on the southern side of the circulation, so the entire Big Island is expecting heavy rain. Locally, cities and towns across the Hawaiian Islands should expect anywhere from 4-12 inches of rain from the system (with heavier amounts in the higher elevations). Flooding is likely with this system, especially in low-lying and particularly susceptible areas.

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Visible satellite image over the Central Pacific, showing Tropical Storm Flossie ready to make landfall. The center of the circulation is actually north of the main core of convection, which looks to be just east of the Big Island (NOAA).


Water Vapor satellite image (same time as above) showing the dry air in the region. Some has been ingested by the storm, and is contributing to the weakening trend. However, the storm still has plenty of moisture associated with it, and will produce several inches of rain over the state (NOAA).


The projected path for Flossie, showing continued west-northwest movement and weakening as it enters the open waters west of Hawaii (The Weather Channel).

Hawaii is no a stranger to tropical cyclones, but a direct hit is rare when you compare the size of the land mass to the vast size of the Pacific Ocean. Direct hits and close calls are uncommon, but like many things in the state of Hawaii, they can happen in waves. Hurricane Iniki struck the island of Kauai head-on in September of 1992 as a Category 4 Hurricane, causing around 2 billion dollars in damage there. Low-grade Tropical Storm Flossie, while not ideal for vacationers, is quite a blessing when you compare it to Iniki and other far more intense storms in the past.

Stephen Bone
Meteorologist