Forecast: Oahu, Kauai face threat of heavy rain, flooding - Hawaii News Now - KGMB and KHNL

Forecast: Oahu, Kauai face threat of heavy rain, flooding

(Image: Hawaii News Now) (Image: Hawaii News Now)

Widespread light to moderate showers have dropped about half an inch on Kauai and Oahu over the last 24 hours.

The instability aloft will intensify today, and that will enhance the shower activity and the possibility of flooding.

Winds are light and variable but should change to trades this afternoon.

High in Honolulu today will be a sticky 82 degrees. The humidity has moved much higher in the last 24 hours.

A band of deep moisture continues to set up over the Hawaiian Islands today as an upper level trough to the northwest of the state slowly swings through the region over the next two days. The atmosphere will become more unstable as the trough passes through the state with increasing shower activity.

The highest rainfall amounts are forecast over Kauai and Oahu with periods of moderate to heavy rainfall expected to elevate the risk for flash flooding through tonight.

The upper trough will pass through the islands on Saturday, bringing drying trends for Sunday and Monday.

Surf is smaller all around. Next advisory swell is forecast for late Sunday/Monday along north and west shores.

Waves today will be 2-4 feet north and south, 1-3 feet east and west.

Flash flood watch for Oahu, Kauai, and Niihau through late tonight. It could be extended and/or expanded. Stay alert and stay safe.

- Dan Cooke

This story may be updated.

Copyright 2018 Hawaii News Now. All rights reserved.

Powered by Frankly