FACTBOX-Storms knock out power to over 580,000 homes and businesses in Pacific Northwest

By Scott DiSavino

NEW YORK, Dec 17 (Reuters) - Severe storms in the U.S. Pacific Northwest and Rocky Mountains knocked out power to around 661,000 homes and businesses on Wednesday, according to data from PowerOutage.us.

That was up from around 581,000 customers out in Washington and Oregon earlier in the day as the storm spread into Idaho, Montana and Colorado. Utilities in Washington and Oregon, meanwhile, have restored some earlier outages. In total, the storm affected around 778,000 customers.

The hardest-hit utilities included Puget Sound Energy in Washington State with around 130,000 of its 1.29 million customers out and Portland General Electric POR.N in Oregon with around 94,400 of 445,700 customers out, according to PowerOutage.us.

On its website, Puget Sound Energy said early morning reports from field crews are of a significant amount of damage, including wires down and uprooted trees. "We currently have 18 substations and 31 transmission lines offline," the utility said.

"Weather conditions are expected to improve today ... We've brought in additional crews from outside our region and are working around the clock to restore service as quickly and safely as possible," Puget Sound Energy said.

Here are the major outages by state: