BURLINGTON, Washington, Dec 12 (Reuters) - Residents and emergency crews in towns along the rain-engorged Skagit River in western Washington state braced on Friday for potential levee failures while National Guard troops assisted in evacuations after days of severe flooding in the Pacific Northwest.

Level 3 "Go Now" evacuation notices have been issued for residents of Burlington, asking them to leave immediately, due to rising floodwaters from Gages Slough.

Drier weather is coming, but flooding effects are likely to continue for days across portions of western Washington state and northwestern Oregon.

Historic rainfall and catastrophic flooding in Washington state forced the entire city of Burlington to evacuate, with members of the National Guard going door-to-door to help people leave.

Authorities are going door-to-door in South Prairie, Washington, in Pierce County, urging residents to leave their homes immediately as water rises there. The Pierce County Sheriff’s Office previously said that at least 25 people have been rescued in the county since Wednesday, including in South Prairie.

More than 100,000 residents were told to leave their homes across Washington State this week as rivers overflowed.