Update: Flood watch extended again, now in effect through today

Update at 7:54 a.m. Oct. 28: The flood watch in effect for all main Hawaiian islands has been extended until 6 p.m. today as flash flooding continues to be possible because an upper low-pressure system remains in the vicinity of the state that is producing unstable conditions within a very moist atmosphere.

Periods of moderate to locally heavy showers are expected.

Rain that occurs over already saturated ground could quickly lead to runoff and flash flooding issues.

Update at 3:47 p.m. Oct. 27: The National Weather Service has extended the flood watch in effect for all main Hawaiian islands until 6 a.m. Monday as flash flooding caused by excessive rainfall continues to be possible.

An upper low remains near the islands and is producing unstable conditions within a very moist atmosphere. This will result in periods of moderate to locally heavy showers statewide through tonight.

Rain that occurs over already saturated grounds could quickly lead to runoff and flash flooding.

Flood prone roads and other low-lying areas could be closed because of elevated runoff and overflowing streams. Urban areas might receive more significant flooding and property damage because of rapid runoff.

The public is advised to monitor later forecasts and be prepared to take action should flash flood warnings be issued.

Update at 8:21 p.m. Oct. 26: The only weather advisory still in effect for the Kaua‘i is a flood watch that was issued Saturday morning for all of the main Hawaiian Islands that lasts through Sunday afternoon.

The National Weather Service forecast office in Honolulu reported a low aloft will move over the islands through Sunday, resulting in an unstable atmosphere.

That unstable atmosphere is what led to the heavy rainfall that fell Saturday afternoon over windward Kaua‘i that resulted a flood advisory.

Flood-prone roads and other low-lying areas might be closed because of elevated runoff and overflowing streams.

Urban areas could also experience more significant flooding and property damage because of rapid runoff.

Update at 1:18 p.m. Oct. 26: A flood advisory is in effect until 4:15 p.m. today for the windward half of Kaua‘i as heavy rainfall moving over the area is forecast to cause at least minor flooding on roads and in poor drainage areas and streams.

National Weather Service radar and rain gauges indicated heavy rainfall just after 1 p.m., especially over Wailua. Rain was falling at a rate near 2 inches per hour in relatively fast-moving showers.

Some locations that will experience flooding include Līhuʻe, Kapaʻa, Kalāheo, Princeville, Kīlauea, North Fork Wailua Trails, Wailua Homesteads, Wailua, Anahola, Hanalei, ʻŌmaʻo, Moloaʻa, Lawaʻi, Kōloa, Poʻipū, Wainiha, Wailua River State Park, Puhi, Hanamāʻulu and Keālia.

The public is advised to stay away from streams, drainage ditches and low-lying areas prone to flooding.

Original post at 8:44 a.m. Oct. 26: A flood watch has been issued for all the main Hawaiian Islands through Sunday afternoon.

According to the National Weather Service forecast office in Honolulu, a low aloft will move over the islands today through Sunday, resulting in an unstable atmosphere.

Conditions will be increasingly favorable for the development of heavy showers and thunderstorms, especially over windward areas.

Flood-prone roads and other low-lying areas could be closed because of elevated runoff and overflowing streams. Urban areas could receive more significant flooding and property damage because of rapid runoff.

A high surf advisory also remains in effect until 6 p.m. today for east-facing shores of a good portion of the state, including those of the Kaua‘i, as a moderate to large, medium period swell continues to slowly decline through the weekend.

Large breaking waves of 7 to 10 feet are forecast this afternoon along eastern shorelines.

Strong breaking waves and strong currents will make swimming dangerous in the advisory areas. The public is advised to heed all advice from ocean safety officials — when in doubt, don`t go out.