Heavy downpours on Kauai prompted Kapaa Middle and High Schools to send students home early on Monday.
The Hanalei River rose rapidly and by 4 p.m. police shut down Kuhio Highway, cutting access to the Hanalei Bridge.
Drivers parked along the highway and waited around in hopes to cross by dinnertime, but the bridge remained closed throughout the night.
"Today had heavier rainfalls than it did yesterday," said Lyndsey Haraguchi-Nakayama of Hanalei Taro and Juice Company.
Haraguchi-Nakayama says her sixth generation family farm rushed to evacuate its tractors and other heavy equipment.
Whenever the valley floods, crop damage is expected.
"We already have more than one field right now that went under water and the seedlings are not salvageable," said Haraguchi-Nakayama.
This all comes after a lightning storm Sunday night knocked out power to several communities.
"The thunder and lightning last night were right on top of us," said Makaala Kaaumoana of Hanalei. "We had a lot of flooding up here. The Kalihiwai River was also flooding, we got a lot of water."
A flash flood warning on Kauai, first posted at mid-day, was extended three times.
Meanwhile, gauges on the Valley Isle showed heavy rains of more than three inches an hour in Upcountry Maui.
All the runoff is expected to turn coastlines brown.
Advisories are posted for Hanalei Bay and for the entire east coast of the Big Island.
The state Health Department advises the public to stay out of brown water in rivers and the ocean as they may contain dangerous pathogens and pollutants.
The Red Cross opened Hanalei Elementary School as an emergency shelter for families evacuated from their homes due to flooding.
More unstable weather is expected Tuesday.
Copyright 2017 Hawaii News Now. All rights reserved.
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