I think the adjective should be horrible, and we would not use any article with turbulence... in England
Isn't turbulentele plural? It should be turbulences are ugly. Or is turbulence uncountable?
Yes turbulence is uncountable in English. And unless you can see it, which I struggle to visualise but with mist or smoke or cloud a descriptive author might, you would not say ugly, but could use a lot of less visual adjectives - terrible, awful, horrible, bad, lousy, frightful, violent, crazy, rough.... I like terrible as it is an alliteration.