One of the biggest summer risks on 14ers are the powerful thunderstorms that regularly form during the afternoon. Known as the ‘Colorado Monsoon,’ these storms produce a great deal of lightning at high altitude. With nothing above tree-line to strike but you, anyone exposed on alpine terrain is at serious risk. In 2015, 15 hikers were injured and one dog killed by a lightning strike just below the summit, and 11 die in Colorado on average every year. Here are tips for dealing with lightning on 14ers, from planning ahead to emergency response if a storm strikes.
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Lightning on 14ers: Some Background Info
To understand lightning on 14ers, you first need to understand the Colorado Monsoon. During warm summer months, from late June through August, the sun gradually warms the mountain rock throughout the day. By noon, the warm rock begins warming the air above, which begins to rise in a column. This creates a cycle of warm rising air, which is the foundation of a thunderstorm system. These key factors: time, moisture and heat are the key to mitigating lightning risk.
Second, you should have a basic understanding on how lightning strikes work. First, a series of ‘leaders’ shoot out from the crowd. Splitting like tree branches, these negatively charged columns of hot air search for the path of least resistance to the ground. Similar, positively charged leaders shoot up from the ground or conductive objects (like you!). Where the two leaders connect, a bolt of lightning strikes. This is why staying off ridges and peaks helps protect you – the bolt is more likely to connect with a higher leader than those emanating from you.
Plan Ahead & Prepare
Lightning safety starts at home with your preparation for the trip. Check the weather forecast each day leading up to your trip, being especially wary of forecasted rain or thunderstorms. Whenever the chance is above 40-50% I recommend postponing. Of course, thunderstorms form in the mountains almost at random during summer months, even when the forecast calls for sunny skies. Take the forecast with a grain of salt, and assume that you may still end up running into storms. Do your due diligence researching your route, packing gear like a rain jacket and maps to make retreat easy should a storm rear its head.
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Start Early, End Early

The single best way to reduce your risk is to start early – aim to summit by 11am, so you can be at or near tree-line before noon. The likelihood of storms developing rises dramatically after 12pm, but they can form as early as 9 or 10am if conditions are poor. The more time you give yourself, the better your chance of success. Don’t be tempted by the many misinformed hikers who start late in the day – stay safe and start early. You should give yourself at least 1 hour to climb each 1,000 feet of elevation: If the peak is a 4,000 foot gain, start by 6:30am-7am (or sooner!).
Watch the Horizon Closely
An early start will help you stay safe but it isn’t a guarantee. The 15 hikers mentioned early on Mt Bierstadt already summited beforet 11:30am when the lightning struck – early, but not unheard of either. It’s not uncommon to see storms developing by 10 or earlier on poor days. For this reason, it’s super important to continue watching the sky and horizon as you hike in case storms begin developing or heading your way. Watch for large, puffy clouds that are growing vertically – that is, they’re developing thunderheads. During breaks, turn around to look behind you – many a 14er hiker has been surprised to find a storm developing directly behind them.
Be Ready to Respond Quickly
If you see a storm developing, you have a few choices to make. You should consider the direction the storm is headed, the current time, your location compared to the summit, and potential bail-out routes should the storm hit you. These are alternative paths down to treeline that save time. Sometimes, especially on Class 2 and 3 routes, there may be no bail out. In this case, you would have to descend the normal route.
If a storm does hit you, and lightning begins to strike in your immediate vicinity, you should use a few last ditch efforts to maintain safety. If in a group, spread out at least 15-20 feet apart so the strike does not hit you all. Continue to descend if possible, but take your time and move slowly and purposefully. You are more likely to trip and fall during a hasty escape than struck directly, so take care. If you are far from treeline and there is intense lightning activity, consider using the position of last resort by crouching and leaning on the balls of your feet to reduce your contact with the ground. Your goal whenever possible should be to continue moving to the relative safety of treeline.
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Lightning on 14ers: Stay Safe!
No amount of lightning preparation can protect you 100%. Any time in the mountains involves inherent risks that we accept. However, all things considered, your risk of a lightning strike is very small on 14ers. With the right precautions, you can reduce it to something negligible. Do you have anything to add on the topic? Share a comment below with your thoughts!