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 1000ís 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.