5.6 — Lightning, Hail and Tornado

Three short-notice hazards, each with a small number of clear rules.

Lightning

The single most useful thing: lightning kills people who were outdoors and thought they had time.

And the survival rate is high — the large majority of people struck by lightning survive — though many are left with long-term effects.

The rule

When thunder roars, go indoors.

If you can hear thunder at all, you are within range of being struck. There is no safe distance at which you can hear it.

And the counting rule — five seconds per mile between flash and thunder — tells you how far away the last strike was, not where the next one will be. Strikes can occur many kilometres from the parent storm, including out of an apparently clear sky.

Where to go

A substantial building with wiring and plumbing — these conduct the current safely to ground.

Or a hard-topped metal vehicle with the windows closed. **The metal shell conducts the current around the occupants. Not a convertible, not an open cab, not a motorcycle.

And once inside: stay off corded phones, avoid plumbing — do not shower or wash up — and stay away from windows and doors.

Where not to go

Under a tree. The classic and one of the most common causes of lightning deaths, because the current travels down the tree and through the ground.

Open ground, hilltops, ridges.

Water — swimming, boating, fishing.

Near metal fences, poles, machinery or equipment, which conduct current a long way.

And an open shelter — a bus stop, a pavilion, a shed with open sides — which offers no protection at all.

If you are caught in the open

Not good options, and here is the best available.

Move away from tall isolated objects and off high ground.

Get to a low area but not one that will flood.

Spread out if you are in a group — several metres apart, so one strike does not affect everybody.

Crouch low on the balls of your feet, with feet together, head down, hands over ears. The point is minimal contact with the ground and no height. Do not lie flat — ground current travels through the earth and lying down increases contact.

And drop metal objects.

After a strike

A person struck by lightning carries no charge and is safe to touch immediately.

Start CPR if they are not breathing (3.2). Cardiac arrest is the main cause of death from lightning and it responds well to resuscitation.

In a group strike, treat the apparently dead first — this is the reverse of normal triage (1.2), because the ones who are moving and moaning are breathing, and the still ones may be recoverable with immediate CPR.

And the 30/30 rule for resuming activity: wait until 30 minutes after the last thunder.

Hail

Rarely fatal and frequently damaging, and the rules are short.

Get inside, away from windows. Large hail breaks glass and comes through with force.

**In a vehicle: pull over somewhere clear of trees, stay inside, and turn away from the windscreen. Lie down across the seats if the hail is large, with your back to the windows.

Do not get out to cover the vehicle. Hailstones can be large enough to cause serious injury or death, and paintwork is not worth it.

And outdoors with no shelter: protect your head, and get under anything solid.

Tornado

Rare in most of the world, devastating locally, and with warning measured in minutes.

The warning signs

A dark, often greenish sky. A wall cloud, particularly one that is rotating. Large hail. A loud continuous roar, frequently described as sounding like a freight train. A visible funnel — and one may not be visible, particularly at night or in heavy rain.

And debris being lifted at ground level, which is sometimes the only visible sign.

What to do

Go to the lowest floor, the most interior room, with the most walls between you and the outside.

A basement is best. Failing that, an interior bathroom, closet or hallway on the ground floor.

Cover yourself. Mattress, heavy blankets, a helmet if there is one — head injury from debris is the most common cause of death.

Get under something sturdy and hold on.

And a bathtub is a genuinely good option in a house without a basement, because it is anchored plumbing.

Where not to be

A vehicle. **Tornadoes lift them. If a tornado is visible and traffic allows, drive at right angles to its path; if not, abandon the vehicle and get to a low ditch, lying flat and covering your head.

Under an overpass. This looks like shelter and is one of the worst places — wind accelerates through the gap and debris is funnelled into it.

A mobile or temporary structure. **These are destroyed by tornado winds and are the single most dangerous place to be. Leave and go to a substantial building or a ditch.

And a large open-span room — a hall, a gymnasium, a warehouse — where the roof has no internal support.

The common principle

Across all three.

The warning is short and the correct action is simple, which means the entire question is whether you act immediately or wait to see.

And in all three, the standard fatal pattern is a person who went outside to look.

What to do with this page

If you can hear thunder, you are in range. No safe distance.

Substantial building or hard-topped vehicle. Not a tree, not an open shelter, not water.

In a group strike, treat the still ones first — the reverse of normal triage.

Hail: stay in the vehicle, back to the windows, and do not get out.

Tornado: lowest floor, most interior room, cover your head — and never an overpass or a mobile structure.

Next: 5.7 — volcano and ashfall, which the brief named and which most people know nothing practical about.