(NewsNation Now) — An unusually strong winter storm is clobbering the Hawaiian Islands and raising the threat of dangerous flash floods, landslides and crashing tree limbs.

Oahu and Kauai saw the brunt of the storm Monday and it is expected to linger throughout Hawaii on Tuesday, bringing with it the possibility of significant flash flooding.

For Maui and the island of Hawaii, which have already been soaked, “it’s not going to take a lot of additional rain to really lead to big problems,” National Oceanic and Atmospheric Administration meteorologist Robert Ballard said.

Mayor Rick Blangiardi signed an emergency proclamation for the City and County of Honolulu Monday night as Oahu experienced hours of heavy rains, strong winds and flooding.

Hawaiian Electric asked hundreds of downtown Honolulu residents to be ready for an extended power outage as their crews work to restore service that was impacted heavily by the continuing rains.

On Maui, more than 2,700 residents living in the Makawao area were impacted by a power outage that began on Sunday. According to Hawaiian Electric, crews are working to fix the outage, and there is no estimated restoration time available.

From the empty shores of Oahu’s Waikiki Beach to the snowy summit of the Big Island’s highest peak, the strong storm left couples without weddings and tourists stuck indoors. 

Weather officials warned that slow-moving thunderstorms, high winds and heavy rains could persist through Wednesday.

“Now is the time to make sure you have an emergency plan in place and supplies ready should you need to move away from rising water,” Gov. David Ige said in a statement.

NewsNation affiliate KHON2 and The Associated Press contributed to this report.