The number of low-visibility hours in Williams Lake, B.C. each wildfire season due to smoky weather. 'Low visibility' is defined as when visibility is between 0 and 6 miles by Environment Canada. Wildfire season in this sample stretches from May to October. 2023 data as of Sept. 21. The chart largely stays below 50 hours until 2010, where it stays largely above 100 until 2023.