The capricious nature of thunderstorms cannot guarantee you absolute protection from being struck by lightning, however, being aware of, and following proven lightning risk reduction guidelines can reduce the risk of injury or death.

If you are outside and you hear thunder or see lightning, the safest thing to do is to either get inside a safe building or to get inside an enclosed automobile. There is nothing you can do to substantially reduce your risk if you remain outside and lightning is occurring.

You are ultimately responsible for your personal safety and you have the right to take appropriate action when you (or your family members) are threatened by lightning.

When thunder roars, go indoors!

Welcome to the Lightning Risk Reduction Outdoors section of the Colorado Lightning Resource Page. This document discusses what you should do if you are outside and observe lightning in the area or hear thunder.

Before discussing lightning risk reduction outdoors, we need to define what a safe location is. The safest location to be in during lightning activity is:

1. An enclosed building,

while the second safest location to be in is:

2. An enclosed metal vehicle.

You want to be able to reach one of these locations if you are outside and lightning begins to occur.

What is a safe enclosed building?
What is a safe enclosed metal vehicle?

Not all types of buildings or vehicles are safe during lightning activity. Click on the links below for examples of unsafe building to be under during lightning activity, and unsafe vehicles to be in during lightning activity:

          Unsafe Buildings

Unsafe Vehicles

The key to Lightning Risk Reduction Outdoors is knowing the answer to the following 2 questions:


1) How far away am I (or the group of people who I am responsible for) from a safe location? and,

2) How long will it take me (or my group) to get to the safe location?

These questions need to be answered before lightning storms threaten. By knowing the answer to the above questions will greatly increase your chances of not becoming a lightning strike victim.

An important thing to remember: Sometimes lightning storms can develop overhead. This means that the first lightning strike from the cloud might be in your immediate location. It is recommended that you should be alert for developing thunderclouds overhead when outdoors. If you see thunderclouds developing or darkening skies overhead, you should implement your lightning safety plan of action.

In addition, there are times when a lightning flash can travel horizontally many miles away from the thunderstorm cloud itself and then strike the ground. These types of lightning flashes are called "Bolts from the Blue" The reason why they are called "Bolts from the Blue" is because they appear to come out of a clear blue sky. Although these flashes are very, very infrequent, they have been known to cause fatalities. Click here for more information about "Bolts from the Blue".

Lightning Safety Guidelines:

The following lightning safety guidelines are broken down for individuals, small groups and large groups. These safety guidlines are for those who are outside and a safe location is nearby. It is recommended that you read all of the safety guidelines.

Lightning Risk Reduction Guidelines: For Individuals

Lightning Risk Reduction Guidelines: For small groups (less than 10 people)

Lightning Risk Reduction Guidelines: For Large Groups 

First Aid Information for Lightning Strike Victims

Lightning Risk Management for Backcountry Campers and Hikers


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