On a crane job the other day, lifting large sections of pre assembled trusses onto a commercial building, I got into a discussion with the contractor after I suggested to him to "hurry the hell up" as it looked to me like the heavy smoke in the area was hiding an approaching thunderstorm, and maybe a gust front. He thought it was just smoke, I was more suspicious.
That's the thing about smoke flying I have experienced, flying into a thunderstorm area, with the smoke disguising exactly what was going on. The first few lightening strikes help to make it perfectly clear what is going on, even to the dimmest pilot 
