The experts at the Bingham Research Center have reported that the chance of ozone exceeding the EPA standard this week is low but what is that based on? They provide the following explanation which is a helpful guide for understanding ozone alerts throughout the winter. They shared that snow plus high pressure equals winter ozone, but we think the likelihood of ozone levels building up significantly in the next week are low for two reasons. First, 1-2 inches of snow will leave lots of exposed vegetation and bare ground, so the snow reflectivity needed to make ozone will be middling at best. Second, yesterday was the winter solstice, so the days are very short and the sun is low in the sky. Ozone needs sunlight to form, and with the sun this weak, it will form very slowly. Thus, even if the snow gives fairly uniform coverage and sticks around, and even if we have sunny, high pressure conditions that create a temperature inversion, ozone will build up under the inversion very slowly, and we will have plenty of notice. To sign up for Winter Ozone alerts, visit
