Understanding Severe Weather Hazards

As winter is coming to an end and the transition to spring begins, the threat for severe weather and flooding will increase over the coming weeks. Let’s review severe weather hazards that will become more prevalent as we enter the transitional season.  

Damaging Winds

Damaging winds within severe thunderstorms are generally defined as wind gusts over 58 mph, but even gusts over 40 mph can cause damage. Winds that reach this speed can break off large branches, knock down, or cause structural damage. In the strongest thunderstorms, wind speeds can reach above 80 mph, bringing the potential for objects to be picked up and flung by the winds. During a damaging wind event, be sure to immediately go inside a sturdy building and move to an interior room or basement with no windows.

Hail

Included in the official severe thunderstorm definition is the ability for storms to produce hail that is one inch or larger. Hail this size can cause damage to plants, roofs and vehicles. Some severe thunderstorms can produce hail larger than softballs, so be sure to move indoors and stay away from windows. 
 

Thunderstorms wouldn’t be thunderstorms without lightning. Lightning strikes the U.S. about 25 million times a year and causes (on average) about 28 deaths in the U.S. each year, severely injuring hundreds more. Despite common myths about lightning, there is no safe place outside (including under trees!) when thunderstorms are in the area, so be sure to remember the phrase: “When Thunder Roars, Go Indoors!”
 

Thunderstorms can also produce heavy rains, which in turn can sometimes cause flash flooding. This would typically occur when thunderstorms with heavy rain move slowly over an area, or multiple storms move over the same area over a short period of time leading to rapid rises in streams, creeks and bayous. Flooding may also sometimes occur far from when the rain fell; this is especially common in the western United States, where low lying areas suddenly get a torrent of water rushing in from upstream. Its important to know your risk if you reside in an area that is susceptible to flooding. Avoid rising creeks and never drive through water covered roads. It only takes one foot of fast-moving water to sweep away cars, while two feet of water can sweep away trucks and SUVs. Remember the phrase, “Turn Around, Don’t Drown!”
 

The most violent of the severe thunderstorm threats, tornadoes pose a significant threat to life and property. Tornadoes are violently rotating columns of air that extend from the base of a thunderstorm to the ground. There are three types of alerts for impending tornadic activity: Tornado Watches, Tornado Warnings, and Tornado Emergencies.

 

Like other watches, a Tornado Watch means that weather conditions could lead to the formation of a tornado. While there may be not immediate actions necessary, it is important be aware of the potential for dangerous weather and be prepared to act if necessary.

 

A Tornado Warning means that a tornado has been spotted or indicated by radar and could be in the area shortly. When a tornado warning has been issued, there is an imminent danger and you should immediately seek shelter in a sturdy structure, preferably in a basement or an interior room away from windows.

 

A Tornado Emergency, on the other hand, is an extremely rare situation with severe threat to human life and catastrophic damage expected from a confirmed, violent tornado. Just like a warning, you should seek shelter immediately in the safest location possible.

 

When severe weather is unfolding, be sure to have a plan of action and way to access weather alerts and warnings in case any severe weather hazards are imminent. 

Source: NWS
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Image: Time-exposure photo provided by the Santa Barbara County Fire Department shows a series of lightning strikes over Santa Barbara, California, on Tuesday, March 5 2019. (Mike Eliason/Santa Barbara County Fire Department via AP)