tempestuous adj.

late 14c., "worldly, secular;" also "terrestrial, earthly; temporary, lasting only for a time," from Old French temporal "earthly," and directly from Latin temporalis "of time, denoting time; but for a time, temporary," from tempus (genitive temporis) "time, season, moment, proper time or season," from Proto-Italic *tempos- "stretch, measure," which according to de Vaan is from PIE *temp-os "stretched," from root *ten- "to stretch," the notion being "stretch of time." Related: Temporally.

"violent storm," late 13c., from Old French tempeste "storm; commotion, battle; epidemic, plague" (11c.), from Vulgar Latin *tempesta, from Latin tempestas "a storm, commotion; weather, season; occasion, time," related to tempus "time, season" (see temporal).

Latin sense evolution is from "period of time" to "period of weather," to "bad weather" to "storm." Words for "weather" originally were words for "time" in languages from Russia to Brittany. Figurative sense of "violent commotion" in English is recorded from early 14c. Tempest in a teapot attested from 1818; the image in other forms is older, such as storm in a creambowl (1670s).