Severe Weather Awareness Week: What makes a thunderstorm severe? - WBTV 3 News, Weather, Sports, and Traffic for Charlotte, NC

Severe Weather Awareness Week: What makes a thunderstorm severe?

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CHARLOTTE, NC (WBTV) -

When determining if a thunderstorm is severe, there are two main criteria that the National Weather Service will look at. How strong are the winds, and how large is the hail?

Wind speeds in a Severe Thunderstorm must be at least 58 mph, or 50 knots. These wind speeds are strong enough to take down tree limbs and injure anyone caught outside. Hail of one inch (quarter sized) is large enough to cause roof damage and is also used as a criteria for a Severe Thunderstorm Warning.

If a warning is issued for your area, you should head inside a strong, sturdy building and wait until the storm passes.

If rotation is detected on radar, then the Severe Thunderstorm Warning will be upgraded to a Tornado Warning.

Lightning, no matter how frequent or whether it's striking the ground, is not used as criteria for a Severe Thunderstorm Warning. That means any thunderstorm could be deadly.

Tomorrow we'll look at one of the deadliest natural disasters: lightning.

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