This year, our region has already seen its fair share of severe thunderstorms and even storms producing tornadoes. Odds are that we will see many more severe storms through summer and into fall. Even though severe storms occur every spring, summer, and fall, many folks either forget or don’t recall all of the weather terms that we use and how to apply them to their safety. So I thought I would write up a quick, down-and-dirty reference guide that you can turn to when severe weather strikes.
Let’s begin with thunderstorms. First, not every thunderstorm that develops becomes severe and a common misconception is that if you see frequent lightning or heavy rain it has to be severe. That is actually FALSE. The truth is our local weather service determines if a storm is severe based on the strength of the wind and the diameter of potential hail. The exact definition are for winds of 58 m.p.h. or higher and/or hail of 1 inch in diameter or larger.
In addition to simply determining if a storm is severe, the National Weather Service distinguishes if the threat of the severe storm is possible or imminent/occurring.
Many times you will hear us on the radio and TV talking about a Severe Thunderstorm Watch when it still looks sunny and calm outside your window. That is because a Severe Thunderstorm Watch means that the ingredients are present in the atmosphere for severe thunderstorms to develop. Simply put, severe thunderstorms are possible in and near the watch area but that doesn’t mean they are occurring or even will occur. Publicizing a watch is our way of giving you the heads up so that you can make a plan to get somewhere safe should storms develop.
Now when a Severe Thunderstorm Warning is issued it means that severe thunderstorms are occurring or are imminent in the warned area. When a warning has been issued for your area, you should put your safety plan into action immediately.
Fortunately, unlike our friends in the Midwest and Plains States, tornadoes are not extremely common. However, as we have already seen just this year, they do occur and you should prepare by having a family plan in place.
Similar to Severe Thunderstorm Watches and Warnings, Tornado Watches and Warnings also follow the same line of thought.
A Tornado Watch means that severe thunderstorms may develop and could be capable of producing tornadoes. Bottom line again is that tornadoes are possible in and near the watch area but doesn’t mean that they are occurring or even will occur. The watch is again meant to get your attention and let you know that the weather dynamics are such that a tornado could be produced if and when severe storms develop. You should already have a family plan in place but this would be the time to locate and inform them of this potentially dangerous situation.
A Tornado Warning on the other hand means that a tornado is imminent or already occurring and to seek shelter immediately. Advances in communication, radars and weather modeling have help to make strides in providing advanced warning for tornadoes. However, the average lead time for a Tornado Warnings is around 13 minutes which makes seconds count. Here is a great page from the Storm Prediction Center in Norman, Okla., that goes into great deal on prevention, practice and what to do during a tornado.
Hopefully this information helps to keep you and your family a bit more informed and safe. Of course you should always tune into ABC 7, NewsChannel 8, and WTOP radio where we will have the latest during any severe weather event.