October may be better known for Halloween or fall colors, but in the Portland metro area we also know it as Fog Month.

Two mornings of thick fog in the Willamette Valley this week slowed traffic and had us reaching for a beanie and extra sweater before walking our dogs.

National Weather Service (NWS) Portland meteorologist Clinton Rockey told PDXtoday this weather pattern should come as no surprise. “This is definitely the time of year — October and early November is the sweet time,” he said, adding that early fall rain provided the perfect conditions for fog to form. “There are three key things you need: wet ground, clearing skies, and light winds.”

Portland records an average of 12 days of fog each October, the most of any calendar month, including six “dense fog” days where visibility drops to a quarter mile or less. So far this October we have witnessed four dense fog days, a long way from the historic record of 16 in 1949. Some readers may also remember October 1986, when Portland shivered through a record 10 days in a row of dense fog.

Rockey, however, sees foggy conditions in a more positive light. “A lot of people — especially kids — love fog. It’s like an Etch A Sketch where you can’t really imagine what’s out there without using your imagination,” he said.

The NWS, however, does not advise you to use your imagination when driving. Instead, during your morning commute, you should:

Reduce your driving speed and use low beams
Leave extra space between you and the vehicle in front of you

Is Fog Month your favorite Portland weather month of the year? We would love to hear from you.