Determining the Threat
How does one determine potential for severe weather for a particular day? The key ingredients for
severe weather include an unstable airmass, a lifting mechanism like a front, and wind shear.
The National Weather Service in Jackson issues a Thunderstorm Outlook for the state every day at 10 am...
more frequently as needed. This product is transmitted to civil defense and emergency management agencies
as well as the media, and is broadcast on NOAA Weather Radio usually between 10 am and 1 pm. The thunder-
storm outlook presents the potential for thunderstorms and severe thunderstorms in the state. Often
ingredients such as airmass instability, lifting mechanisms, and wind shear are discussed in the product.
When conditions are favorable for severe weather, a severe thunderstorm or tornado watch is issued. A watch
issuance is a clear sign that severe weather may occur in or near your area.
There are signs in the sky that one can look for to determine the potential for severe thunderstorms. Before
thunderstorms develop, look for the following: sunshine which leads to airmass instability(however, airmass
instability can also come from cooling aloft, so dont assume no threat of severe weather if the sky is cloudy
all day); and gusty surface winds or rapid movement of low level clouds which indicate strong winds aloft;
When thunderstorms begin to develop or approach your area, look for tall crisp, clear "cauliflower" shaped
clouds with a "boiling appearance. Thunderstorm clouds that appear fuzzy indicate evaporation. a sign of a weak
thunderstorm.
When a Watch Is Issued...
Monitor local weather conditions for rapid changes. Monitor NOAA Weather Radio or local TV/radio stations for
possible warning issuances. Be prepared to act quickly when a warning is issued.
When a Warning Is Issued...
Remain calm, but move quickly to a safe shelter. Follow the instructions given in this pamphlet and by local media.
Make sure you can access the latest information via a portable radio or NOAA Weather Radio.
If Severe Weather Occurs In Your Area...
Remain in safe shelter until the storms have passed. Once it is safe to leave shelter, report any severe weather
to the National Weather Service, or report it to your local law enforcement agency and ask them to relay your
report to the National Weather Service.
Return to Severe Weather Awareness Page
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