On Friday at 7:38 a.m. a dense fog advisory was issued by the National Weather Service in effect until noon for West Central Willamette Valley, East Central Willamette Valley, Benton County Lowlands and Linn County Lowlands.

The advisory is in effect until 2 p.m. A dense fog advisory is issued by your local National Weather Service office when widespread dense fog develops. When this happens, visibilities frequently drop to one-quarter of a mile or less. These conditions make travel difficult. Take extra caution when on the road or avoid driving if possible.

Dense fog is expected to persist until 1 p.m. Thursday in the central Willamette Valley, including in Salem, and in the Southern Willamette Valley, including Eugene. The air stagnation is expected to last until 10 a.

An updated dense fog advisory was issued by the National Weather Service on Thursday at 11:49 a.m. in effect until noon for Central Douglas County.