Summer in the mountains brings gorgeous days, but also some of nature's worst weather tantrums. Heat-induced thunderstorms are frequent, violent, and can develop in less than an hour. Lightning, hypothermia from sudden temperature drops, and slips on slick terrain represent very real hazards.
### Warning Signs to Watch For The sky speaks to anyone who listens. Watch for the appearance of *cumulus congestus* — those cauliflower-shaped clouds expanding vertically by midday. If your hair stands on end or you hear a low, metallic buzzing sound (St. Elmo's fire), a lightning strike is imminent.
### The Emergency Checklist in Exposed Terrain If you cannot drop down into the valley or reach a managed mountain hut in time, implement these strict rules immediately:
* **Leave summits and ridges:** Descend as low as possible, away from high, prominent points. * **Isolate yourself from metal objects:** Drop your trekking poles, ice axe, or internal-frame pack at least 30 metres away from you. * **Never shelter under a lone tree:** It acts as a perfect lightning rod. Avoid shallow rocky overhangs too, as electrical currents can arc right across the opening. * **Adopt the safety stance:** Crouch down on top of your foam sleeping pad or backpack (to isolate yourself from the ground) with your feet tightly together and your head tucked in. Never lie flat on the ground.
"In the high country, it's better to ruin a beautiful hike out of caution by turning back at noon, rather than finding yourself trapped on a 3,000-metre ridge at 3pm."
Anticipation remains your ultimate line of defense. Check localized mountain forecasts the morning of your trip and plan to start hiking at dawn so you are already down — or safely sheltered — before the critical mid-afternoon hours hit.