Air Stagnation Advisory? (Portland: camp, allergies, air pollution)

[dejo44]

Because I am a future transplant to Portland, I check the forecast often to get an idea of the weather there. I see Portland has an air stagnation advisory this week. I wonder if it's the same as ozone action days we have here in Ohio. In Ohio this only occurs in the summer on very hot humid days. I just assumed the air quality was good there (especially in the winter) so I haven't researched this aspect of my move. Does this occur often in Portland?

[HonuMan]

We do get stagnant air advisories occasionally, and they're probably the same as what you get in Ohio. An air mass will hang over the city (we're in a valley), auto exhaust will build up, and we'll get the ozone effect from the sun. Usually they occur in the summer during a heat wave. Winter ones are rare, but they do happen. They last a few days at most. The vast majority of the time, Portland has good air quality. If you suffer from allergies, pollen and molds can be a problem, but no more so than other areas of the country where lots of vegetation grows.

[Or3g0n]

Yeah I'm a native Portlander and been here for my whole life. The air stagnation is very rare here, occurring ranging from three to five days each year. Right now we are having a smog, it's because of temperature inversion, which makes Mt. Hood (1 hour east) at camp at 7,000 ft getting 66 degrees instead of 30s and valley getting up to only 40s. Opposite effect, warmer air once you go higher instead of getting cold. Fog is usually a result of temperature inversion. I really hate air pollution, trust me, our air is like... most cleanest air you will ever breathe on average day. You can see mountains clearly or anything, hundreds of miles away. I've been to Midwest and East Coast for a few weeks, I have never seen that much smog before and I've never seen Portland getting that bad compared to what I saw in Midwest and East Coast.

[Nell Plotts]

Ya, we are anal-retentive about air pollution. Possibly one of the reasons why old line industries aren't happy here. On the other hand employers who need clean rooms, very clean rooms, appreciate the culture.

[figmalt]

It happens in both the summer and winter, but it's compounded in the winter because we typically have a lot of cloud cover. Clouds + engines + wood burning stoves + inversion = stuffy air.