The National Weather Service issued a high surf advisory for the main Hawaiian islands and an earlier flood advisory for Kauai was canceled at 5:15 p.m.

The high surf advisory is in effect through 6 p.m. Wednesday as forecasters expect a northwest swell to push surf to 5 to 8 feet along east-facing shores.

Heavy showers are possible on all islands through Thursday, along with vog and hot, humid conditions.

At 11:12 a.m. radar showed a band of rain about 8 miles northwest of Lihue. All parts of the island are under the advisory, which is in effect until 5:15 p.m.

The state Department of Land and Natural Resources closed the Kalalau Trail Tuesday because of heavy rain and the potential for flash flooding. Parks staff will re-evaluate trail conditions Wednesday morning to determine if the trail should be reopened.

Overnight and this morning, heavy rains fell over parts of Oahu.

Forecasters said radar showed a band of nearly stationary, heavy rain near Maunawili at 2:30 a.m. lingering over the area. A rain gauge at St. Stephens recorded rain rates of 1.75 inches an hour.

The rains eased at about 6 a.m. and forecasters canceled a flood advisory for the southern Koolaus.

In the 24-hour period ending at 5 a.m., Maunawili got nearly 4.5 inches of rain. St. Stephens recorded 2.3 inches and 1.2 inches fell at the Oahu Forest National Wildlife Refuge in the northern Koolau range.

Forecasters said unstable atmospheric conditions and an increase in moisture around the islands is creating an increased chance of rain through Thursday. 

The cooling tradewinds are weakening and light, variable winds will allow seabreezes to blow in more muggy weather until the tradewinds return, forecasters said.

Haze from Kilauea volcano may also move over the western islands.

The lighter winds are bringing a greater chance of afternoon clouds and showers over leeward and interior portions of all islands, with a slight chance of thunderstorms near Kailua-Kona on the Big Island.

"Not much changes in the weather scenario is expected Wednesday, so the islands can expect to see pretty much a repeat of today’s weather, with more widespread land and sea breezes and afternoon clouds and showers," the weather service said in a forecast discussion on its website.