What are damaging winds?

What are straight-line winds?

Straight-line winds are generally any thunderstorm wind that is not associated with rotation, and is used mainly to differentiate from tornadic winds.

What causes straight-line winds?

Most straight-line winds are a result of outflow generated by a thunderstorm downdraft.

Why is the wind gust limit set at 58 mph?

In the 1950’s and 1960’s, there were three types of convective watches that could be issued: Tornado Watches, Public Severe Thunderstorm Watches, and Aviation Severe Thunderstorm Watches. At first, the public severe thunderstorm watch wind criterion was 75 mph, while the limit for aviation watches was 50 mph. Negotiations with the Air Force raised the minimum speed required for an aviation watch to 58 mph (50 knots) in 1962. In 1970, the Aviation Severe Thunderstorm and Public Severe Thunderstorm watches were combined into a single Severe Thunderstorm Watch, with a minimum wind gust criterion of 50 knots, to reduce confusion.

 

What is the difference between a microburst and a downburst?

A downburst is the general term for all localized strong wind events that are caused by a strong downdrafts within a thunderstorm, while microburst simply refers to an especially small downburst that is less than 4 km across.

We had damaging winds in our area; how can we tell if they were caused by a tornado or microburst?

Check with your local National Weather Service Forecast Office to see if they conducted a damage survey in your area.