Many houses were destroyed by the fury of the typhoon.
The typhoon raged, destroying many houses.
新型ウイルスの猛威が世界中に広がっている。
The fury of the new virus is spreading across the world.
This area is exposed to devastating floods every year.
The rampage of the new virus continued for several months.
猛烈 is an adjective meaning 'fierce, violent' and can describe almost anything intense, whereas 猛威 is a noun naming the destructive force itself, most often paired with 振るう.
Compound of 猛 (fierce, violent) and 威 (power, authority). The exact historical derivation is uncertain, but the combination naturally conveys overwhelming destructive force.