Hawaii ushered in the new year with a weekend of pouring rain and booming thunder.

“Welcome to winter in Hawaii,” said Jeff Powell, shift supervisor at the National Weather Service in Honolulu.

Powell said that a Kona-low storm passing through the islands brought heavy rain and thunder to Oahu.

“It’s a low-pressure system that’s off to our northwest,” he said. “It’s unstable, it’s moist, and so what we’ve seen the past few days is just manifestations of that.”

Oahu experienced record rainfall last month during “Kona low” conditions on Dec. 6, leading to flooding, power outages, sewer discharges and property damage. That storm was worsened by a mixture of strong winds and high tides that combined with the rain.

But Powell said the weekend’s weather wasn’t anything unusual.

“Kona lows are not uncommon for Hawaii. We even have a (term) for it, right? ‘Kona lows,’” he said.

However, even regular storms can be intense. The weekend saw heavy rain and thunderstorms, and 34-knot winds.

On Saturday the state Department of Transportation briefly closed Pali Highway town-bound between Castle Junction and the hairpin turn due to rocks and mud that spilled onto the roadside at around midday amid heavy rainfall. Road crews removed debris and downed roadside trees before reopening the Pali at about 5:30 pm.

The Navy also warned that the weather could be disruptive to its efforts to flush its drinking water system that serves 93,000, which was recently contaminated with jet fuel that spilled from its Red Hill fuel storage facility.

“With that we’re going to be very closely watching the amount of water going into the storm drains,” said Capt. Darren Guenther of Navy Region Hawaii during a Facebook Live town hall meeting on Friday. “There’s a possibility if we get a lot of rain, we may need to slow some of our flushing operations so we don’t over burden the drains.”

But Powell said the coming days should bring clearer skies as the Kona low passes by.

“It’s destabilizing our airmass right now but will gradually drift far enough away that this type of weather will literally just dry up,” Powell said, noting that starting today Oahu residents can expect to see less stormy conditions. “It won’t be dry, but it won’t be quite as unstable, and this really wet stuff that we’re seeing (Sunday) and especially (Saturday) will moderate significantly.”