Lightning Risk on an Exposed Ridge
You are leading a group of 7 on a ridge hike above treeline. The weather forecast predicted afternoon thunderstorms. It is 13:00, and you are 1 km along a 5 km exposed ridge with no shelter. You hear thunder and see dark clouds approaching from the west. The time between lightning and thunder is 15 seconds, decreasing. The group is fatigued, and one person is slightly altitude sick. The nearest safe shelter (a hut) is 2 km back the way you came, and the ridge continues for another 4 km. What do you do?
1. Assess the lightning risk and decide on the best course of action.
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Lightning risk: 15 seconds between flash and thunder means the storm is about 5 km away (sound travels ~1 km per 3 seconds). Decreasing time means it's approaching. Exposed ridge is dangerous; you are the highest point. Options: retreat to the hut (2 km back) or continue (4 km forward). Retreat is shorter but still exposed for 2 km. Continuing is longer exposure. Best action: descend off the ridge if possible to lower elevation, but if not, retreat to the hut is likely safer due to shorter distance. Move quickly but safely. Avoid being the tallest object; spread out if caught. Do not shelter under isolated trees. Keep moving to reduce exposure time.
2. If caught in the open during the storm, what lightning safety measures would you take?
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If caught in the open: descend to lower elevation if possible. Avoid ridges, peaks, isolated trees, and water. Spread the group out (at least 15 m apart) to reduce multiple casualties. Assume the lightning crouch: squat low, feet together, hands on knees, head down, minimizing contact with ground. Do not lie flat. Remove metal objects (packs with metal frames, ice axes) and place them away. Stay crouched until 30 minutes after last thunder. Monitor group for signs of strike (confusion, burns) and be prepared to give first aid and CPR.