This from Steve Redick:
This was Sunday morning, 12/9/18. Some kind of mattress warehouse that was fully sprinklered and metal clad. Initial response was an automatic alarm I believe. Not much to be seen from the outside but got to watch truck 26 do some aggressive ventilation with the aerial as well as some saw work on the side of the building. Here’s a few images and all the rest including video can be seen here:Steve