Five areas of interest will be covered in this writing on general thunderstorm hazards including:
1. Lightning
2. Visibility, Slick Roads
3. Roof Damage
4. Wind Damage
5. Water Damage


Lightning is one of the primary killers from thunderstorms. Lightning does not require a severe thunderstorm warning. ANY storm can produce lightning (severe or non-severe). Lightning also strikes with little or no warning. Many lightning deaths occur when it seems the storm is “winding down and the rain has slackened or stopped”. For these reasons (produced from any thunderstorm / little or no warning / thinking storm is over), lightning is responsible for dozens of deaths each year. Storm deaths from flooding and tornadoes are often heard about more partially because several deaths often occur at once and the storm event is often on people’s mind. Lightning tends to kill one person at a time (although multiple deaths at once do occur) and can occur from ordinary storms that are not on people’s mind as much.

People commonly go outside during a thunderstorm such as to go to the car, participate in outdoor activities or to walk to another location. The thinking can be, “getting struck by lightning is like the odds of winning the lottery… it is not going to happen to me”. This can make people feel more comfortable when outside during a storm given that the odds are very low of getting struck. The threat from lightning can not be visually seen like with many of the cases with other weather events (tornado seen approaching, flooding seen in road) thus the victim has basically no time to make a decision to avoid lightning. The decision to avoid lightning has to be made before going outside or being stuck outside. This can be difficult to do but can mean the difference between life and death since a great percentage of lightning deaths occur outside (although a few deaths occur inside also such as when lightning travels through plumbing or electrical wire).


Another general thunderstorm hazard is driving. The storm does not have to be severe to cause significant driving problems. One problem with driving in the rain is visibility (VIS). Even with good windshield wipers it can be frustrating to keep constant visibility through the changes in intensity of rain. Splashing and spraying from nearby vehicles can also reduce visibility. It is important to drive slower and more cautiously when it is raining. Since the visibility is reduced, it is important to turn on headlights during these rainy and wet conditions so that other drivers can see you better. Fogging up inside the car can be a problem during rain. This is because the humidity is high and it is easy to condense moisture on glass. Be familiar with the proper and best techniques to unfog the windows in your particular car in order to prepare for this potential problem.

An additional problem when it rains is that the roads become slicker. Water reduces friction between the tires and the road. The condition of the tire will play a role in how significant the problem with wet roads become. It should be assumed the cars around you and your car will have less friction with the road. This results in longer stopping distances when putting on the brakes. It also means it can be easier to lose control of the vehicle. The problem with less road friction is another reason to drive slower and with more caution during rain.


Thunderstorms add wear and tear to a roof. It may take one storm to damage a roof or it can be the cumulative impact of storms over many years or a combination of both. There are several ways in which the weather elements can damage a roof. They include the impact from hail, damage from wind, thaw and freeze opening up cracks, water leaking through the rotting wood, and long term damage from the sun. Many of these factors contribute to the roof needing to be replaced after several years. One big storm though can do the damage all at once. The big events are large hail and severe wind. A hail storm or wind storm may be significant enough that the roof needs immediate attention due to leaks that are opened by the hail or wind. A leaking roof will lead to continued and further damage each time it rains.

Roof damage can result in 1000s of dollars of needed repairs, thus roof replacement is big business. The proper home insurance can substantially reduce these costs to the home owner when a replacement is needed. A new roof adds value to the home and is a primary defense from the weather. Over many years though the weather wins and a replacement is needed.


A 58 mph wind or above is a severe wind. A severe thunderstorm warning will be issued when wind speeds are this high or greater from a thunderstorm that has developed. Wind speed lower than this can also cause considerable damage and death. Thus, any thunderstorm is capable of producing damage and death. One threat results from the wind blowing objects down. One of the most common objects that can be blown down includes tree branches. Tree branches are extremely heavy and will severely damage anything they fall on. Locations with big and tall trees are especially in danger of having trees fall on objects below. These objects can include houses and cars. The damage produced from any one tree can result in 1000’s of dollars of damage. A person under a tree can be injured or killed by a falling limb. This makes it very important to keep trees pruned. This reduces the chance of a weak limb falling on property or a person. Wind can also produce damage to fencing, sheds and any fragile materials exposed to outside air. Precautions should be taken before a storm strikes such as reinforcing fencing, putting away loose outside materials, pruning trees, and having cars safely parked.


There are several ways in which thunderstorms can produce water damage. One type of damage can be done to landscaping and gardens. The runoff from rain will tend to flow in thin and long bands. Where the water is flowing, erosion will occur. If the soil is loose, then this runoff will quickly erode an area. This can result in the loss of soil, displacement of soil and significant time in order to repair the damage.

Rain events can also hide pot holes in the road. With the pot holes hidden, cars will run into them causing potential damage to the car and an enlargement of the pot holes. It is not uncommon to notice more and bigger pot holes after rain events. Wet roads can also make it more difficult to see painted road lines and to see reflection from headlights.

Water damage also occurs when water seeps into areas that are supposed to be water proof. This can result in damage to houses, window frames, doors and cars. It is important to check to see if a seal is maintained over time. If the seal is compromised it should be fixed quickly to reduce damage.