Tropical Storm Moke expected to bring up to 15 inches of rain in Hawaii: Maps and projected path

Tropical Storm Moke is expected to deliver heavy rainfall and gusty winds this weekend as it skirts just south of the Hawaiian Islands in the wake of serious damage delivered by Hurricane Lala.

Moke packed maximum sustained winds of 50 mph as of midday Saturday and was expected to strengthen throughout the day, according to the National Hurricane Center. The storm is not expected to make landfall in Hawaii, but will still deliver rain and wind to the Big Island on Saturday night and early Sunday and then the other islands early next week.

“Recent impacts from Tropical Storm Lala mean that even light to moderate rain and wind could trigger flooding, debris, downed trees, roadway issues and power outages,” Maui County Mayor Richard Bissen said in a statement. “County departments have been preparing for Tropical Storm Moke, and we’re asking our community to do the same.”

“This rainfall may produce life-threatening flooding and mudslides for the windward and southeast Big Island, especially in steep terrain and over areas that were affected recently by Lala,” according to the National Hurricane Center.

The islands, especially the Big Island, were hit very hard by Hurricane Lala just last weekend. A hurricane hasn’t made direct landfall in the state since Iniki in 1992, but the eye of the then-Category 1 Hurricane Lala passed just 30 miles off the Big Island’s coast, bringing wind gusts over 80 mph and torrential rain, with some areas seeing more than 3 feet. Kapalua, located in Maui County, was hit with 48 inches of rain over the weekend. 

“We know many in our community are experiencing storm fatigue and still recovering from last weekend’s weather system, so mahalo for continuing to look out for one another and staying prepared — especially because we are up against an above-average hurricane season,” Bissen said.

The rainfall totals from Moke won’t be as high, but will still be dangerous, especially in conjunction with the already saturated ground. Rainfall totals across the hard-hit Big Island will span 5 to 10 inches with up to 15 inches in some locations, according to the National Hurricane Center. Eastern Maui, the second-largest of the islands, will receive 3 to 6 inches on average. The rest of the islands could see 1 to 2 inches of rain.

Hawaii activated its joint information center on Saturday, just days after deactivating its center for Lala. The information center is responsible for coordinating updates for the public from the Hawaii Emergency Management Agency.

The Hawaii Emergency Management Agency also said Saturday that Hawaii Gov. Josh Green had submitted a request with the White House asking President Trump to issue an emergency declaration for both Lala and Moke. 

“Our teams are working on two fronts: helping communities recover from Lala while preparing for Moke,” Green said in a statement. “We have submitted our request for federal assistance to bring additional resources to Hawaii.”     

The islands are paying a price from an El Niño climate pattern, via warming waters in the eastern Pacific Ocean. Warm ocean waters are the essential fuel for tropical cyclone development, which makes this El Niño phase perfect conditions for an increased hurricane season in the region.

Because it reduces vertical wind shear, meaning change in direction of winds at higher levels of the atmosphere, an El Niño climate pattern allows for tropical systems that develop in the region to avoid getting “blown over” and falling apart.