Skies clear Wednesday, with highs near 90 by Saturday

For the longest time my father, who traveled the nation as VP of sales for a printing company, told me that “Californians don’t trust air they can’t see.” Vehicle exhaust created a perpetual brown haze over cities from L.A. to Denver as recently as the 1970s, before the Clean Air Act slowly cleaned up air quality.

Now the problem is often heat waves and heat bubbles setting up over the western U.S. and Canada, creating a ripe environment for megafires — vast wildfires started by lightning that are difficult or impossible to extinguish, resulting in thick plumes of dirty air thousands of miles downwind.

One such tentacle of soot will be with us much of this week, it appears. A few more obligatory thunderstorms fire off later Tuesday over southern Minnesota, but skies clear Wednesday with sunshine and a late-week warming trend back into the 80s. Saturday looks like the more lake-worthy day, with weekend highs near 90 degrees.

If the smoke keeps up, meteorologists may be sharing the air quality index (AQI) along with daily highs.