The National Weather Service has issued a dense fog advisory for Baker County.
The persistent high pressure has created a temperature inversion that has trapped cold and moist air near the ground in the region's valleys, an ideal combination for fog to form.
The advisory will be in effect until 10 a.m. today.
Visibility measured at the Baker City Airport has been as low as one-quarter mile this morning.
Similar weather is forecast for the next several days.
More information is available at http://www.wrh.noaa.gov/boi