described roughly/uncontrollable fire
Adumbrate is an academic word that is used to foreshadow something to occur, or as it is used in the sentence here, meant to give a vague description or outline of something. The usage of this word is extremely low according to normal corpus linguistic standards. The root of the word is "umbra" and from the Latin, shadow. And as such is the other more frequently used intention of the word - to foreshadow. In this context of foreshadowing, it is meant to tell what is likely to occur in a novel or story line.
Conflagration on the other hand is a powerful fire. It is meant to be used to describe a fire which is incredibly destructive and intense. A good synonym would be "inferno", as this also includes connotations with hell and/or the devil. A conflagration would be a spectacle to watch and in extremely dangerous to be in or around.
