Portland, Oregon, will face potential flooding from Tuesday through Thursday as the record snowfall from the previous week, kept in place in part by over two weeks of freezing temperatures, will face rapid melting due to temperatures above freezing and heavy rain from an incoming storm system, according to Accuweather. While the brunt of the rain from the coming storm is expected to fall over Oregon’s coastal range, Portland residents face areal flooding with drains potentially blocked by snow and ice as the heavy rains begin and the snow begins to melt. Portland faces flooding just days after catastrophic flooding in Central and Northern California.
As of 3:22 p.m. on Sunday, January 15, 2017, the National Weather Service has issued a flood watch for Northwestern Oregon and Southwestern Washington, including the Oregon Coast Range through the Washington Coast range, and including the Portland and Vancouver metro areas. The watch states that freezing temperatures will rise above 8,000 feet on Monday night, leading to rapid snow melt. That melt will be combined with between one and three inches of rain to make the situation worse.
For the Portland metro area, Johnson’s Creek becomes a focal point for concern, a little over a year after flooding in December, 2015. Areas along Johnson’s Creek have become regular sites for homeless people to camp. Portland Fire and Rescue is reaching out to those homeless communities to assist in evacuation.
PF&R Outreach will be engaging homeless along Johnson Creek. The thaw will cause waters to rise dangerously; high risk of drowning. #alert
— Portland Fire&Rescue (@PDXFire) January 14, 2017
While Portland faces up to three inches of rain with the coming system, the Oregon Coast Range could face up to five inches. Rivers of concern include the Grays river in Wahkiakum County, the Lower Nehalem and Wilson rivers in Tillamook County, the Upper Tualatin River in Washington County, the Mary’s River in Benton County, and Johnson’s Creek, which runs through both Clackamas and Multnomah counties. Portland’s last catastrophic flooding occurred in 1996.
The National Weather Service bulletin includes a warning regarding landslides as well.
“Landslides and debris flows are possible during this flood event. People… structures and roads located below steep slopes… in canyons and near the mouths of canyons may be at risk from rapidly moving landslides.”
The potential for flooding follows on the heels of Oregon Governor Kate Brown declaring a state of emergency in Portland and other locations in Oregon after record snowfall on January 11, 2017. The City of Seattle, Washington, sent snow removal equipment and crews to assist in clearing the roads in the Portland metro area. The storm also toppled trees across Portland and in surrounding areas. Multnomah County homeless shelters were 45 percent over capacity, and needed help from other organizations to provide adequate shelter.
According to Willamette Week, meteorologist Matthew Cullen believes that Portland could experience potential for widespread urban flooding, but also admits that calculating the danger for flooding along the Willamette and Columbia Rivers would be premature. Cullen says that while the snow melt will contribute to flooding, areas with heavy rainfall will become areas of concern. That means that while Portland will face the potential for widespread urban flooding, the Oregon Coast Range, with an expected rainfall of up to five inches, could see rivers overflowing their banks.
The National Weather Service warns residents in Portland and other flood watch areas across Oregon and Washington to monitor local flood reports for a flood warning. Residents in areas prone to flooding should be prepared to take action in the event of flooding. A flood watch means that there is potential for flooding based on current forecasts, but it does not guarantee that flooding will occur in the Portland, Oregon, metro area. That will depend on the amount of rainfall that the coming system ultimately drops on Oregon, and the speed at which the snow melts.
[Featured Image by Don Ryan/AP Images]