Smoke front:

Few interesting things about this smoke front.
(i) Dixie fire in the northern california grew rapidly on Aug 05th afternoon when the small-scale trough was passing through this area.  The smoke was locked into this low circulation.
and the low carried this blob to the east across Nevada and Utah.

(ii) In the WBB camera there visibility decreases slowly and then suddenly like a cold front , very thick smoke engulfs the Salt Lake City. Ahead of the front the wind was southerly westerly. Though  southerly the interaction across the frontal boundary created smoke to be present but at smaller values. This is similar to tempeature and mositure interaction across 
the frontal boundaries. The smoke made the mixing process visible.

(iii) Over california the SW winds carried the smoke to the north but wrapped it into the low. Through cyclonic circulation and sinking, this smoke was thickest behind the front.