Lightning casualties are largely preventable, and the recommended precautions rest on specific reasoning.
The thirty-thirty rule
Sheltering when thunder follows lightning within thirty seconds.
Which corresponds to strikes within roughly ten kilometres.
Waiting after the last thunder
Strikes occurring well after a storm appears to pass.
Which is when a substantial share of casualties occur.
Safe shelter
Substantial buildings and hard-topped vehicles.
Which conduct current around occupants.
Unsafe shelter
Trees, open shelters and small structures.
The single most useful rule
If you can hear thunder, you are close enough to be struck.
Which is the whole of the guidance in one sentence and is the version safety organisations now lead with.
Waiting thirty minutes after the last thunder before returning outside addresses the strikes that occur behind and ahead of the visible storm, which is when a large share of casualties happen.
Why vehicles work
The metal shell conducting current around the occupants.
Which is why convertibles and open vehicles do not.
Indoor precautions
Avoiding corded equipment and plumbing during storms.
Which is a real if small risk.
Survival and injury
Most strikes survived with lasting effects.
Sport and outdoor events
Published suspension protocols.
Why people take the risk
Lightning feels like a remote hazard, storms are frequently visible for a long time before arriving, and the instinct is to finish what you are doing.
Which is why casualties cluster in outdoor recreation and work rather than in dramatic circumstances.
The activities that appear most often in casualty statistics are ordinary: fishing, sport, gardening and standing outside watching the storm.
Group activities
Someone designated to monitor and call a halt.
Which sports governing bodies now require.
If shelter is unavailable
Avoiding high ground, isolated trees and open water.
Which reduces rather than removes risk.
Helping someone struck
Casualties carrying no charge and needing immediate resuscitation.
A general note
National safety organisations publish detailed guidance.
Why understanding the system matters
Weather warnings are the output of a large, expensive, internationally coordinated system that most people interact with only through an app icon. It is one of the clearest examples anywhere of publicly funded science producing something everyone uses daily without noticing.
The practical value of understanding it is in reading warnings correctly. A cone is not a map of the storm, a watch is not a warning, a hundred-year flood is not once a century, and a radar app is not a warning service. Each of those misunderstandings has cost lives, and each is corrected in a sentence.
Where the authoritative information is
National meteorological services issue the warnings, publish the forecasts, explain the products and archive the data, all freely. Local emergency management agencies publish evacuation zones, shelter locations and preparedness guidance specific to the hazards where you live.
Those two sources answer almost every question anyone has about weather risk, and both are considerably more reliable than aggregated coverage, which frequently reproduces the misunderstandings described above.
A general note
Warning terminology, alert thresholds and emergency procedures differ between countries and between agencies. Anything with safety consequences should be checked against the service responsible for the area you are actually in.
How the warning system is actually organised
National meteorological services observe, model and forecast; they issue watches, warnings and advisories against defined criteria; and local emergency management agencies decide what action to take in response, including evacuations, shelter openings and road closures.
Those are two different organisations with two different jobs, which is why a national forecast office issues a hurricane warning and a county decides who evacuates. Knowing which one to follow for which question saves a great deal of confusion during an event.
What is worth doing before a season starts
Find out which hazards actually affect where you live, check whether your address sits in a flood or surge zone, identify where you would shelter, confirm that emergency alerts are enabled on your phone, and know how you would get information if the power and the network both failed.
None of that takes long, all of it is free, and every element of it becomes considerably harder to arrange once a warning has been issued. Emergency managers say the same thing after every major event: the households that coped were the ones who had decided in advance.
Where the authoritative information is
National meteorological services issue the warnings, publish the forecasts, explain what each product means and archive the underlying data, all freely. Local emergency management agencies publish evacuation zones, shelter locations and preparedness guidance specific to the hazards where you actually live.
Between them those two sources answer almost every question anyone has about weather risk, and both are considerably more reliable than aggregated coverage, which routinely reproduces the misunderstandings that cause harm.
A general note
Warning terminology, alert thresholds and emergency procedures differ between countries and between agencies, and they are revised as understanding improves. Anything with safety consequences should be checked against the service responsible for the area you are in rather than against a general description.