Hawaii braces as Hurricane Nolo threatens catastrophic flooding

Hawaii's Big Island is on high alert as Hurricane Nolo inches closer, threatening catastrophic flooding and powerful surf. The Category 2 storm, with winds of around 105 mph, is positioned roughly 155 miles south of South Point and moving at a mere few miles per hour. While forecasters expect Nolo to turn westward while staying south of the islands, its slow movement raises concerns over prolonged rainfall.

The National Weather Service warns of potential catastrophic and life-threatening flash flooding, particularly on the Big Island where intense rainfall could cause landslides, overflowing streams, and rapid rises in dry channels. A hurricane watch and tropical storm warning remain in effect for Hawaii County, as Nolo's outer rain bands approach the island.

Forecast models predict widespread rain totals of 15 to 20 inches across the Big Island, with isolated amounts reaching up to 35 inches. Maui is also bracing for heavy rainfall, with several inches expected and potentially higher totals in mountainous areas.

Authorities urge residents to avoid unnecessary travel, monitor emergency alerts, and prepare for rapidly changing conditions. People living in flood-prone areas are advised to be ready to evacuate to higher ground and to never attempt to cross flooded roads, as water depth and currents can be hard to judge. Emergency officials are especially concerned about communities near streams, low-lying roads, and steep slopes, where saturated ground could increase the risk of rockfalls, mudslides, and fallen trees. Heavy rainfall could also isolate communities if roads become impassable.

Alongside the rain, dangerous ocean conditions are expected, with large swells generated by Nolo creating hazardous surf. High-surf advisories cover the east and southeast-facing coasts of Hawaii Island, Maui, Molokai, and east-facing shores of Oahu and Kauai. Strong currents and waves breaking along coastal roads or low-lying areas could add to the challenges posed by the heavy rainfall.

Nolo's slow pace is a significant factor in the forecast, as tropical systems moving slowly near mountainous islands can deliver repeated bands of moisture over the same locations. Hawaii's terrain can intensify rainfall as moist winds rise over volcanic slopes, leading to sharp differences in rainfall totals over short distances.

The Weather Prediction Center notes that the greatest threat of heavy rain and flooding lies across the Big Island and Maui, while other islands face lower rainfall totals and isolated flooding. Due to uncertainties in Nolo's exact path, caused by interactions with surrounding atmospheric systems, officials stress that dangerous conditions could extend far from the storm's center.

Strong and gusty winds are possible across the island chain through the weekend, with tropical-storm-force conditions posing risks to trees, power lines, and exposed infrastructure in areas nearest to the hurricane.