Storms Gilma and Hector weaken but still pose a threat to Hawaii

A pair of tropical systems are forecast to further lose strength as they approach the islands of Hawaii, lessening chances of dangerous weather conditions as the state faces a rare cluster of storms over Labor Day weekend.

Tropical Storm Gilma, the closer of the two storms, has weakened in recent days after it peaked in strength as a Category 3 hurricane last weekend. Federal forecasters project Gilma will be downgraded from a tropical storm on Thursday or Friday, when it’s expected to begin dumping rain over the islands.

Hector, formerly a tropical storm, dissipated early Thursday morning more than 1,000 miles from Hilo, Hawaii, according to the Central Pacific Hurricane Center, which has released its final update about the storm. Cold water east of Hawaii is one of the main culprits causing the weakening.

On Friday, Gilma is forecast to track north of Hawaii, unleashing heavy rain and gusty showers, according to AccuWeather. Since the storm no longer has a strong eyewall, its impacts will be limited. However, the storm could still trigger flash floods and pose a potential threat of mudslides.

“One key point to consider even with a poorly organized tropical feature, such as a tropical rainstorm that passes just to the north of the islands, is that some of the south-facing slopes of the islands may get more rain than if a hurricane, such as Hone, was passing by to the south,” AccuWeather lead long-range meteorologist Paul Pastelok said.

In addition to dumping heavy rain over the islands, Gilma could alleviate drought conditions in some “hard-to-reach areas,” according to AccuWeather. Last week, Tropical Storm Hone lashed the Big Island with Hawaii as it passed to the south as a hurricane, causing flooding and knocking out power to thousands of homes and businesses. The storm also dumped enough rain to cause authorities to discontinue several wildfire red flag warnings.

Wildfire dangers are top of mind for Hawaiians, especially when strong storms pass offshore. Last year, the winds of Hurricane Dora, which stayed hundreds of miles off the coast of the Hawaii islands, contributed to the deadliest wildfires in the U.S. in over a century.

The Big Island is forecast to begin receiving thunderstorms and showers late Thursday and Friday before the storms spread over the other islands over the holiday weekend, AccuWeather said. Ahead of the rain, Gilma is expected to produce rough seas and strong surf along the coast.

Forecasters say Hector, now a tropical rainstorm, will unload more heavy rain and winds across Hawaii beginning Sunday and continuing into next week – starting just after Gilma moves away from the state. The rain could exacerbate any ongoing flooding as the storm passes either to the north of Hawaii or directly over the islands.

This weekend could be a historic one for Hawaii, as it has never had more than two tropical storm systems pass close to the islands during previous hurricane seasons, according to AccuWeather. Additionally, the last time two tropical systems storms hit the islands within a week was in September 1992.