Hawaii island got the brunt of the precipitation Sunday in the form of heavy rainfall and, on its summits, snowfall, while rain fell incessantly over the other islands, further saturating the ground.

The National Weather Service extended a flood watch until Monday afternoon for all the Hawaiian Islands, while the Big Island’s flood warning was expected to be lifted for all parts of that island by Sunday night.

A flood watch means conditions are favorable for life-threatening flash flooding. The Weather Service said the atmosphere is unstable and wet, and the ground, especially in windward and upslope areas, is soaked from all the recent rainfall.

A 72-year-old driver was trapped inside a bus that stalled early Sunday morning along Highway 11 in Kau while attempting to drive through floodwaters.

The water was 5 to 6 feet high, a Hawaii County fire official estimated. The area was prone to flooding due to prior heavy rain, which covered the roadway.

Firefighters rescued her and she was uninjured.

Some Hawaii island rain gauges (48-hour precipitation totals ending at 1 p.m. Sunday) measured in the 20-plus-inch range, with the Saddle Quarry gauge falling just shy of 30 inches with 29.12 inches. Hakalau hit 26.39 inches. Mauna Kea’s summit reached 24.59 inches, and Pahala got up to 20.3 inches.

For comparison, the 24-hour record rainfall in the U.S. was on Kauai at Waipa Garden on April 14 to 15, 2018, when 49.69 inches fell.

The Weather Service says showers are expected to gradually diminish today into Wednesday, but tradewinds are expected to remain locally strong and gusty. However “unsettled” weather with more rain could return Thursday and Friday, but with lighter winds.

Police closed Highway 11 at 7:29 a.m. Sunday near Kawa Flats in Kau. It remained closed between mile markers 57 and 61 as of 4:25 p.m. Sunday.

The Weather Service said Kawa Flats, Naalehu and Pahala were in the flood warning zone.

Hawaii County police closed Highway 19 in both directions in the Laupahoehoe Gulch area due to a landslide late Saturday night, leaving drivers with no alternate route until it reopened three hours later.

Police also closed, at 6:23 a.m. Sunday, both lanes on Highway 19 near mile marker 47, north of Honokaa, due to a large fallen tree, until 10:12 a.m. Sunday.

The Department of Public Safety canceled visits to the Kulani Correctional Facility due to fallen trees and hazardous conditions along Stainback Highway, which leads to the prison.

Meanwhile on Oahu, two mudslides on Pali Highway forced the closing of one Kailua-bound lane for several hours. Upper Nuuanu got 14.8 inches of rainfall in 48 hours as of 1 p.m. Sunday.

First responders on Oahu were kept busy with calls for fallen trees and branches, which got dangerously close to power lines.

The Weather Service warns, “Rainfall and runoff will cause hazardous driving conditions due to ponding, reduced visibility and poor braking action.”

It recommends avoiding streams, drainage ditches and low-lying areas prone to flooding.

The flood advisory for windward portions of Hawaii island was in effect until 8 p.m. Sunday due to the significant ponding in communities from windward Kohala to Hilo.

Water levels in streams and rivers were still very high, the Weather Service said.