In addition to lightning, high winds, hail, and tornadoes, summertime thunderstorms also bring the threat of flooding and flash flooding to northern New England. In the summertime, most flash floods are caused by heavy, slowly moving thunderstorms which can produce excessive rainfall in an area in just a short period of time. For more info see our Flood Safety page: www.maine.gov/mema/hazards/natural-hazards/flooding/flash-flood-safety.