National Weather Service United States Department of Commerce

 

Severe Weather Preparedness Week in Southern New England: April 22th - 26th, 2024
For more information, please visit our efforts at making a Weather-Ready Nation.
Also please consult additional Severe Weather Safety Tips than those below including Ready.gov information.


The National Weather Service in Norton will feature a different Severe Weather related topic each day during the Severe Weather Awareness Week.


DAY 1 - SEVERE THUNDERSTORMS
 

A severe thunderstorm is defined as a thunderstorm that produces wind gusts of at least 58 mph and/or hail 1.00 inches in diameter or larger, the size of a quarter. Severe thunderstorms can and occasionally do spawn tornadoes.

A Severe Thunderstorm Watch is issued by the Storm Prediction Center in Norman Oklahoma for large portions of the region when the potential exists for severe thunderstorms. A severe thunderstorm warning is issued by the local National Weather Service forecast office, such as in Norton, when severe thunderstorms are imminent based on radar or already occurring based on spotter observations.

Note that torrential downpours of rain that cause flooding are not part of the definition of severe weather. They would prompt the issuance of Flood or Flash Flood Warnings, but not Severe Thunderstorm Warnings. It is important to note that frequent lightning also is not a criterion for what is termed severe weather. Of course, lightning can be extremely dangerous, but every thunderstorm has lightning. That is what causes the thunder. It is not practical to issue a warning for every thunderstorm, thus we issue Severe Thunderstorm Warnings for those storms that could produce large hail and/or damaging winds.

NOAA Weather radios, with warning alarm tones, will alert you when a Severe Thunderstorm Warning is issued. However, they will not sound an alarm for non-severe thunderstorms, which still can produce deadly lightning. We recommend that lifeguards at beaches and pools have hand-held lightning detectors. The same is true for athletic coaches, camp directors, and parks and recreation workers. Even without equipment, you can protect yourself by moving indoors to a place of safety at the first rumble of thunder. If you can hear the thunder, the storm is usually close enough for you to have the potential to be struck by lightning.