There a Dense Fog Advisory up until noon today through the local area, extending down through the Willamette Valley to Eugene. Extremely thick fog formed in the area overnight, with visibility less than a quarter-mile in some spots. Forecasters say that they expect this dense fog to linger through most of the morning, so you’ll need to be extremely careful on the morning commute; slow down, increase following distance between cars and use your low beams for driving. Highway 30 near Columbia City was closed for nearly an hour after what Oregon State Police describe as a “serious injury crash.” There’s also an Air Stagnation Advisory up for this area and the I-5 corridor until 4 pm on Saturday. The advisory extends down through Clark County and the Willamette Valley. The Weather Service says that a very stable air mass and light winds will make for stagnant air conditions. There may be some light rain to help things on Friday, but they don’t expect air conditions to improve before Saturday.