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Special Report on Central and Eastern Pacific Tropical Cyclones

Dangerous tropical cyclone Iselle taking aim on the Hawaiian Islands

Hurricane Iselle is weakening, although will likely bring blustery winds, heavy rains, and high surf conditions to Hawaii in the Thursday-Friday time frame…while tropical storm Julio will follow in Iselle’s wake during the upcoming weekend.

PDC Global Hazards Atlas displaying Tropical Cyclone Positions and Segments, and Estimated Winds (TAOS Model) layers for Hurricane Iselle, Tropical Storm Julio, and Tropical Depression Genevieve

PDC Global Hazards Atlas displaying Tropical Cyclone Positions and Segments, and Estimated Winds (TAOS Model) layers for Hurricane Iselle, Tropical Storm Julio, and Tropical Storm Genevieve

The eastern Pacific is warmer than normal, and as a result is pumping-out tropical cyclones left and right. Earlier in the 2014 hurricane season, these storms were sticking pretty close to Mexico, moving generally north and north-northwestward along the coast. Recently though, they’ve been moving westward out into the open ocean away from Mexico. As a matter of fact, they’ve been migrating through the eastern Pacific…right over into the central Pacific.

One of the most recent of these storms to push into the central Pacific, was tropical cyclone Genevieve, which passed far enough south of the Hawaiian Islands…that there was no influence. However, it seems to have set a precedent, with many tropical disturbances, and even tropical storms and hurricanes following in Genevieve’s wake. The latest of these tropical cyclones, hurricane Iselle, will soon be bringing a definite weather threat to Hawaii.

Iselle was churning the waters of the eastern Pacific into a wild state, as it’s counterclockwise winds were at a category 4 strength! As expected however, this system has peaked in intensity, and will be weakening throughout the remainder of its life cycle. At the time of this writing, and based on the latest Central Pacific Hurricane Center (CPHC) advisory #22, winds were still strong enough to make it a category 2 hurricane – with 110 mph sustained winds…and even higher gusts.

As you can see below, flooding seems to be the primary threat to the Hawaiian Islands! The CPHC, at the time of this writing, has issued the following statements in response to this approaching tropical cyclone:

NWS Hydrologic OutlookHeavy Rain and Flash Flooding possible Thursday and Friday

Tropical Storm Warning…Thursday through Friday over Hawaii’s offshore waters

Tropical Storm Watch…in effect for the Big Island – which means that tropical storm conditions are possible within the next 48 hours

Flash Flood Watch…for the State of Hawaii – Hurricane Iselle will bring heavy rains to the islands – from 4am Thursday through 6am Friday

This continues to be a strong hurricane, which has now moved out of the eastern Pacific into the central Pacific. This crossing point is the 140W line of longitude…or about 1000 miles east of Hawaii.  Hurricane Iselle peaked in terms of winds earlier in the day yesterday, and will slowly diminish in strength going forward – which is a very good thing for the Hawaiian Islands!

Iselle will likely remain a hurricane through Wednesday evening, and by Thursday morning, it will weaken back into a tropical storm. It will remain a tropical storm thereafter, as it migrates through portions of the Hawaiian Islands into Friday. A tropical storm is an organized system of strong thunderstorms with a defined surface circulation and maximum sustained winds between 39 and 74 mph. The Hawaiian Islands will also see high surf arriving ahead of this tropical storm, breaking along the southeast and easterly shores for a few days.

Here’s the latest IR satellite image of hurricane Iselle:

Meanwhile, the models are showing yet another tropical cyclone moving westward into the central Pacific, a couple of days behind Iselle. This next system is a tropical storm called Julio…and will become a hurricane by Wednesday morning. Julio could bring another round of heavy weather to the islands later this coming weekend. There’s still some minor uncertainty about exactly where tropical storm Iselle will strike here in Hawaii, or if it will slide by just to the south of most of the islands. Either way however, Hawaii likely will see wet and blustery weather, with high surf conditions along our east facing beaches during the Thursday-Friday time frame, and then again later this weekend as Julio moves close…or over the islands.

Here’s the latest satellite image of tropical storm Julio:
Finally, the storm that went by to the south of the Hawaiian Islands recently, named Genevieve, is located well to the west-southwest of the Hawaiian Islands. It began in the eastern Pacific, and has almost passed through the entire central Pacific, on her way towards the western Pacific…which is a very long life span in terms of tropical storms! This storm is of no threat to the Hawaiian Islands, although open ocean vessels should be giving a wide berth to this strengthening storm. As a matter of fact, it may reach typhoon strength briefly before passing over cooler sea water temperatures, which will help put an end to its long lasting journey.

Here’s a satellite image of tropical storm Genevieve: