Eastern Michigan University Environmental Health & Safety While
all thunderstorms are dangerous, the National Weather Service
(NWS) considers a thunderstorm severe if it: - Produces hail at
least three-quarters of an inch in diameter. - Has winds of 58
miles per hour or stronger, or - Produces a tornado.
Thunderstorms generally occur during the warm months; however,
they can occur at any time during the year. More people are
seriously or fatally injured by lightning from thunderstorms
than by any other weather condition. During a storm, stay
informed of weather conditions. Have a portable radio available
and listen to the local station (WEMU 89.1 FM) for
watches/warning issued for the area. The following
watches/warnings may be issued: Thunderstorm Watch: Severe
thunderstorms are possible in the area. Watch the sky and stay
tuned to WEMU 89.1 FM for additional information. Watches are
intended to heighten public awareness and should not be confused
with warnings. Thunderstorm Warning: Severe thunderstorms are