Risk & Rescue
Lightning Is A Terrain Problem Before It Is A Weather Problem
Thunderstorm risk in the mountains is managed by scheduling and position rather than by reacting, because by the time a storm is overhead the options have already narrowed.
Lightning kills a small number of Americans each year, and outdoor recreation accounts for a large share of those deaths. The management strategy is almost entirely about timing and position, not response.
Mountain storms follow a daily rhythm
Across much of the American West, summer thunderstorms build through the day as solar heating drives convection over high terrain, then fire in the afternoon.
The pattern is reliable enough to plan around, which is the origin of the alpine start. Summits are reached in the morning because afternoons are when the sky closes.
Different regions run on different rhythms. The Southeast and the Front Range have their own patterns, and local forecast discussions describe them explicitly.
Position is decided long before the storm
The dangerous places are summits, ridges, exposed slabs, isolated trees and open water. Reaching lower and less exposed ground takes time nobody has once a storm arrives.
That is why the decision point is the turnaround time set at the start of the day rather than the moment thunder becomes audible.
Parties that treat the turnaround time as advisory reliably discover the flaw in that reasoning on the descent.
Ground current is a separate mechanism
A strike does not only injure the person hit. Current spreads through the surface and can travel through wet rock, cracks and standing water to people nearby.
This is why groups spread out during a storm, and why crouching on an insulating item on the smallest possible footprint is the widely taught position.
It is a last-resort posture rather than a safe one, and every source teaching it says so. The goal is to never require it.
The counting rule is a spacing estimate
Sound travels roughly a mile every five seconds, so counting between flash and thunder gives an approximate distance to the strike.
The widely promoted guidance is to seek substantial shelter when the interval is short and to wait a substantial period after the last thunder before resuming.
Neither part is precise. They are simple rules chosen to be usable by people under stress, which is a design decision rather than a scientific claim.
Strike survival is common enough to matter
Most people struck by lightning survive, often with lasting neurological effects. That means the aftermath of a strike is a live rescue rather than a recovery.
People struck may be in cardiac arrest while others nearby are stunned, and they carry no residual charge, so immediate care is safe to provide.
Managing that scene draws directly on wilderness medical training and on getting a call out early, since multiple casualties may be involved.
