pyrocumulonimbus/ˌpaɪɹəʊˌkjuːmjʊləˈnɪmbəs/EtymologyFrom pyro- + cumulonimbus.nounAn extreme manifestation of a pyrocumulus, generated by the heat of a wildfire, that often rises to the upper troposphere or lower stratosphere.“An analysis of how this tornado formed sees several factors joining forces: the preexisting winds and local topography, a pyrocumulonimbus storm developing, and the addition of hotter-burning fuels as the fire hit groups of houses.”