Many flash floods, including those that occurred over parts of New England and the mid-Atlantic states during June 2006, and in Colorado's Big Thompson Canyon in July 1976, are the result of thunderstorms that ____.
A) contain no lightning
B) form in a dry air mass
C) move slowly
D) have weak or non-existent downdrafts

Question

Quizplus · Accepted Answer

Flash floods caused by thunderstorms result from a large amount of rainfall in a short period of time. Thunderstorms that move slowly have more time to deposit excessive rainfall in one area, leading to flash flooding. Thunderstorms with weak or non-existent downdrafts can also contribute to flash flooding as the rain is not pulled down to the ground as quickly, allowing it to accumulate and potentially cause flooding. However, the presence or absence of lightning and the surrounding air mass do not necessarily contribute to the formation of flash floods caused by thunderstorms.

Many Flash Floods, Including Those That Occurred Over Parts of New