The Hawaiian islands have been put on alert as a rare tropical storm approaches the state, the Central Pacific Hurricane Center (CPHC) reported early Sunday (July 28).
Tropical Storm Flossie was located less than 535 miles east of Hilo and or around 720 east of Honolulu and was moving to the west at 20 mph with maximum sustained winds of 65 mph as of the 5 a.m. HST advisory.
Sustained winds with Flossie had reached as high as 70 mph on Friday before the storm weakened as it moved into a more unfavorable environment for intensification.
While Flossie remains well-developed, it is expected to undergo gradual weakening as it moves over the islands on Monday.
“Water vapor imagery shows Flossie entering an area of increasingly dry air aloft, associated with a nearly stationary ridge aloft just west of the main Hawaiian islands. As Flossie moves west, this ridge is likely to impart increasing north to northeasterly shear over the system and intensity models continue to indicate a gradual weakening of Flossie,” said Tom Birchard, a forecaster at the CPHC.
A tropical storm warning has been issued for Hawaii and Maui counties including the islands of Maui, Molokai, Lanai and Kahoolawe ahead of Flossie’s impacts on Monday. A tropical storm watch is in effect for Oahu.
The National Weather Service (NWS) also issued a statewide flash flood watch in anticipation for the potential of flooding.
“Heavy rain associated with tropical cyclone Flossie will bring the threat of widespread heavy rain that could result in flash flooding,” the NWS said.
“The rain will be widespread will affect both the upper and lower elevations. The heavy rain will also fall over urban areas in the lower elevations, which will be more susceptible to flooding problems,” the NWS explained.
The threat for tropical storm-spawn tornadoes and or waterspouts are also possible over the next few days.
Residents are advised to secure all loose items including lawn furniture, garbage cans, boats and other items and to be prepared for tropical storm conditions with possible flooding.
It is rare for a tropical storm or hurricane to strike Hawaii due to the cool waters that typically lie to the east.
Only two hurricanes have made landfall in Hawaii since 1950 and both arrived from the warmer waters to the south.
Hurricane Iniki from 1992 was not only the last of these two hurricanes, but also the last hurricane or tropical storm to slam Hawaii.
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