Forecast: Powerful Kona low meanders off of the islands, most intense rain will now focus over the western end of the state

HONOLULU (HawaiiNewsNow) - A Kona low will linger just west of Kauai with a slow westward drift lasting through Wednesday. A large band of heavy rain associated with this low will also track slowly westward across the state. Within the last 36 hours, we have received 14 inches of rain over Maui County and about 3 to 14 inches of rain over Hawaii Island. So far, 7 inches of rain has fallen over Oahu and 1-3 inches over Kauai, and we can potentially add an additional 5 inches of rain over the western end of the state since there are nocturnal thunderstorms firing up. Now the focus will be Oahu and Kauai into the next 24 hours. Tomorrow a disturbance moves just to our north bringing heightened instability over the western end- so that means more thunderstorms can fire up and some heavy downpours. And more spotty over the eastern end with clearing skies.

Expect widespread heavy rainfall with this system, especially under the large heavy rain band, capable of producing catastrophic flooding, and strong southwest winds through Wednesday.

The heaviest rainfall was over Hawaii and Maui Counties this weekend and know those converging winds and most severe weather will slowly drift westward into Oahu and into Kauai into the night (it will be quiet at times with a little bit of a lull mixed with sporadic overwhelming intense rainfall rates) but another round due in late tonight into Tuesday for the western end.

Improving weather conditions will start over the eastern side of the state by late Tuesday with drier air slowly spreading into the western islands on Wednesday.

More typical trade wind weather will return from late Wednesday onward.

A large north swell has peaked and will begin to decline through Monday.

A high surf advisory is in effect for most west-facing shores from Maui to Kauai. Abnormally high ocean levels are coinciding with seasonal peak high tides the next couple of days.

Although the north swell is declining, some elevated coastal run up may occur at peak high tide times early Monday morning.

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