The Willamette River Rose 2 Feet in a Day, Thanks to Summer Deluge

After an overnight gusher of unseasonal rain, Portland authorities delivered a stark warning Saturday: Stay out of the rivers or they’ll sweep you away.

An “atmospheric river”—essentially a firehose of rain directed straight into Oregon off the Pacific Ocean—has left the state’s actual rivers running dangerously high and fast, the National Weather Service said today.

“A series of wet storm systems will result in rising rivers across the Pacific Northwest over the next several days,” the NWS’s Portland office wrote June 11. “As this water feeds into the Columbia River, expect the Columbia River to approach minor flood stage between Vancouver and Kelso late in the weekend into early next week.”

Meteorologists expect the Columbia to run as high as it has in at least three years, it wrote. As of 1:30 pm Saturday, the Columbia River at Vancouver had risen 1.47 feet in 24 hours, the NWS said. In Salem, the Willamette River had risen 2.22 feet in the same day.

In the past 24 hours, much of Portland received more than 1.5 inches of rain, a record for the date. The Grand Floral Parade on Saturday morning dodged the heaviest downpours, but more rain is expected to fall tonight.

Early reports indicated that none of Portland’s rivers had reached flood stage—and at noon Saturday, the NWS called off a flood warning for Johnson Creek in Southeast Portland.

But it’s unusual for rivers to run so high during peak summer recreation season, and officials hinted at worry that unassuming revelers would try something dumb, like tubing down the Sandy when it looks like the Oompa Loompas’ chocolate river.

“Marine deputies and lifeguards are warning swimmers to stay away from local rivers for several days after immense rainfall and rapid snowmelt,” the Multnomah County Sheriff’s Office warned on social media. “The Sandy River (pictured) is especially swollen, fast-moving and numerous hazards exist.”

The NWS similarly urged boaters to exercise caution. Logs and rocks won’t be as visible in the high water, and could damage boats.

The rivers may also effect commutes, the NWS wrote: “Interstate 5 bridge lifts are more frequent during periods of high flows on the Columbia River.” (Willamette River bridges will see delays of their own. It’s Fleet Week.)

UPDATE: 5:30 pm: On Saturday afternoon, Portland Parks & Recreation announced that the swollen Willamette River forced the city to close the floating portion of the Vera Katz Eastbank Esplanade.

“As the water rises from recent ongoing rains, it has lifted the floating path so that the connecting portions between the bridge and fixed, concrete sidewalk are approaching unsuitable angles,” parks bureau spokesman Mark Ross wrote. “Portland Parks & Recreation’s primary concern is for the public’s safety and appreciates people adhering to the temporary closure.”