Category 5 Monster Stalls Off Hawaii's Big Island — Forecasters Warn of 'Catastrophic' 35-Inch Flooding
Hurricane Nolo exploded into a Category 5 storm overnight before grinding to a near-standstill south of the Big Island, and forecasters say its outer bands could dump enough rain to trigger life-threatening flash floods before it even makes its closest approach.
Hurricane Nolo roared to Category 5 strength overnight, packing 160 mph winds as it churned toward Hawaii's Big Island — then did something forecasters didn't expect: it stopped. By Saturday morning the storm had weakened to a "high-end" Category 2 with 105 mph winds, but instead of moving on, it parked itself roughly 145 miles south of the island and stayed there, according to the National Hurricane Center's latest advisory.
That stall is the dangerous part. The longer Nolo hovers offshore, the longer its outer rainbands get to wring themselves out over the same stretch of ground. The Hawaii Tribune-Herald reports forecasters are warning of "catastrophic and life-threatening flash flooding" across parts of the Big Island, with rainfall totals as high as 35 inches possible in the wettest spots.
The numbers behind the warning
The eastern and southern Big Island are bracing for an additional 4 to 8 inches of rain, with isolated pockets seeing 10 inches on top of what's already fallen — pushing storm-total rainfall into the 10-to-20-inch range and as high as 25 inches in a few locations, per FOX Weather's tracking of the storm. Forecasters are also flagging a storm surge of 1 to 3 feet along parts of the coast, a threat that grows more serious if it lines up with high tide.
"CATASTROPHIC AND LIFE-THREATENING FLASH FLOODING" — National Weather Service warning for the Big Island
Nolo is the fourth tropical system to threaten Hawaii this season, part of an unusually active stretch for the islands. Weather.com notes the storm is forecast to pass well south of Kauai even as it continues to lash the Big Island's eastern and southern coasts with damaging wind and rough surf.
County officials have not yet ordered evacuations tied specifically to Nolo, but residents in flood-prone gulches and near streams on the Big Island's Hilo and Puna sides have been urged to prepare for rapid water rises and to avoid unnecessary travel. Hurricane warnings remain in effect for the Big Island, with tropical storm warnings extended into Maui County as Nolo's reach widens across the state.
What's next depends on whether Nolo resumes a northward track or continues to loiter offshore. Either way, forecasters say the flood threat will persist through the weekend regardless of the storm's exact wind speed, since for this storm it's the rain — not the wind — driving the most serious danger.