PORTLAND, Ore. (KOIN) — The National Oceanic and Atmospheric Administration has issued a flash flood watch for areas of Southwest Washington, including the greater Vancouver area, the Cascades and their foothills.

The ongoing atmospheric river is forecast to dump heavy rainfall onto the area’s burn scars Friday night. Approximately 3 to 4 inches of rain are predicted to hit the area by 11 p.m. As much as 5 inches of rain will be possible in localized areas.

“Residents near the Nakia Creek, Siouxon, Kalama, Sunset and Black Hole burn scars should prepare for potential flooding impacts,” the National Weather Service reports. “Be sure to stay up to date with information from local authorities. Heavy rainfall could trigger flash flooding of low-lying areas, urbanized street flooding and debris flows in and near recent wildfire burn scars.” 

The flood watch will remain in effect until the storm subsides, reportedly around 11 p.m. Friday.

A flood advisory has also been issued for areas of Northwest Oregon and Southwest Washington, including Clackamas, Clark, Clatsop, Columbia, Cowlitz, Multnomah, Pacific, Skamania, Tillamook, Wahkiakum, Washington and Yamhill Counties.

Minor flooding is expected to occur in low-lying and poor drainage areas and where river or creek flows are elevated.

Pools of rainwater are expected to collect in urbanized areas. Cities most likely to see flooding include Hillsboro, Oregon City, Battle Ground, Washougal, St. Helens, Kelso, Sandy, Astoria, Seaside, Woodland, Warrenton, Vernonia, Castle Rock, Cannon Beach, Stevenson, Long Beach, Cascade Locks, Garibaldi, Manzanita and Cathlamet.

“Be aware of your surroundings and do not drive on flooded roads,” the NWS said. “Flooding is occurring or is imminent. It is important to know where you are relative to streams, rivers, or creeks, which can become killers in heavy rains. Campers and hikers should avoid streams or creeks.”

The flood advisory will remain in effect until 10 p.m. Friday.