One other thing I forgot to mention, is that the major fire that is 12 miles away from me, has been roaring for 8 days, so isn't in the category of "sudden events like fires". Forecast information is only valuable if the accuracy is validated by looking at it when the forecast date arrives. If the forecast is close then it is valuable, but if it is way off then it isn't. In fact it can actually be harmful. I am hoping that Windy.com wants to be recognized as a quality site and grow because of accuracy measured over time. Garbage in garbage out applies to the PM2.5 data.