Hurricane Ignacio Still Strengthening in the Pacific; May Threaten Hawaii Next Week

August 28,2015

Highlights:

• Ignacio was upgraded to a hurricane Wednesday night and is located roughly 720 miles east-southeast of Hilo, Hawaii as of 11 p.m. EDT Friday.
• Hurricane Ignacio is forecast to slowly intensify through Saturday before gradually weakening thereafter.
• Ignacio is not a threat to land this weekend, but may come close to Hawaii as early as Monday or Tuesday.
• Interests in the Hawaiian Islands should monitor the progress of this latest hurricane.

Latest Storm Information

Ignacio continues to move through a favorable environment for tropical cyclones well east-southeast of the Big Island of Hawaii.
(MAP: Follow Hurricane Ignacio with our new Interactive Storm Tracker)
The airmass that Ignacio is moving through has relatively low wind shear, or the change in wind speed with height. When wind shear is too significant, it can effectively rip apart the structure of a tropical cyclone. With limited wind shear in the storm's path, Ignacio should continue to get better organized over the next few days as it moves west-northwest.
Hurricane Ignacio is moving over warm water and a moist environment. All of these factors favor additional strengthening over the next day or so, potentially becoming a Category 2 hurricane or higher on the Saffir-Simpson Hurricane Wind Scale.
Later this weekend, conditions are expected to become less favorable, with an increase in wind shear and slightly cooler water temperatures, so a weakening trend is likely as it approaches the Hawaiian Islands.
Over the next few days, Ignacio will track to the west-northwest due to a strong subtropical ridge of high pressure to the north of the system. On Friday, computer forecast models were fairly consistent with a track north of the Hawaiian Islands.

Another Hawaii Threat?

Although the official track takes Ignacio just a few hundred miles northeast of Hawaii by early next week, there is still time for this to change. The forecast position from the National Hurricane Center for Monday has Ignacio coming close to or passing just north of the Big Island.
Based on the current forecasts, at least some impacts in terms of increased surf appear probable for Hawaii, particularly the east and northeast-facing shores of the Big Island. If the storm maintains intensity as it approaches, gusty winds and locally heavy rain could also be a concern.
Several tropical systems have threatened Hawaii over the past few weeks, but most of them changed course and/or weakened before directly impacting the islands.
Climatologically speaking, virtually all hurricanes near the Hawaiian Islands since 1950 have approached from the southeast, south or southwest. Those approaching from the east tend to either weaken quickly or shift north of the islands. Iselle in 2014 was one notable exception, however.
(MORE: Hawaii's Hurricane History)
Nonetheless, interests in Hawaii should continue to monitor Ignacio into early next week.

Projected Path

MORE: Hurricane Satellite Imagery