The cooling, cleansing trade winds did not return as expected yesterday, leaving Oahu covered with volcanic haze for a second straight day.

But the National Weather Service said light trade winds should return today and clear up the skies over the island. The trade winds are forecast to increase gradually over the weekend, but remain light at 10 to 15 mph, said Maureen Ballard, NWS forecaster.

"As the trades start to build, we will see the vog start to dissipate over Oahu," Ballard said. "Of course it will still linger over the Big Island as it always will."

The trade winds also should make things less humid and sticky, Ballard said.

"Just in time for the weekend, things should start to get better," she said. "But we are still talking about light trades through the weekend, so it's still going to feel warm and you're not going to get a huge relief, But it will be certainly better than it's been the last couple of days."

The muggy, hazy conditions were caused by a front northwest of Kauai. The front caused the winds to shift to a southerly direction, which brought the volcanic emissions from the Big Island.

Conditions yesterday weren't as bad as they were Wednesday, when visibility at the Honolulu International Airport dipped to 2 miles. Yesterday, visibility never dropped below 5 miles, the NWS said.