Keep an eye on the hillsides, coastal Oregon: the National Weather Service says there will be heavy rains in the area Thursday night, which can lead to landslides and debris flow.

The weather service issued a flood warning for Tillamook and a flood watch for the northern Oregon coast and Coast Range, both of which will last through 2 p.m. Friday.

The National Weather Service warns that the expected heavy rains Thursday evening could trigger landslides, especially in areas that have had wildfires or have been burned.

Debris flows are fast-moving, destructive landslides that can contain large rocks or logs, the weather service said. The debris can get transported down hillsides for more than a mile, and moves faster than a person can run. The weather service said people living below steep slopes and near the mouths of canyons may be at higher risk, and advised those in watch areas to stay alert by tracking flood watches, listening for unusual sounds like trees cracking or boulders knocking together, and watch for sudden increases in water flow in nearby creeks and streams.

The weather service also advised people to assume that roads are not safe, and to watch for falling rocks and debris on the road.

—Jayati Ramakrishnan; 503-221-4320; jramakrishnan@oregonian.com; @JRamakrishnanOR

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