Recognizing the Warning Signs

Lightning rarely strikes without warning. Before a bolt hits near you, there are almost always signs that a dangerous situation is developing. Learning to recognize these signs is the first step in protecting yourself and those around you.

The most obvious warning is the sight and sound of an approaching storm: darkening skies, towering cumulonimbus clouds, and distant rumbles of thunder. But there are more immediate, closer-range signals that indicate lightning could strike within seconds. If you notice your hair standing on end, feel a tingling sensation on your skin, hear a crackling or buzzing sound in the air, or see a blue glow on metal objects (known as St. Elmo's fire), a lightning strike is imminent and you must act immediately.

These physical sensations occur because the electrical field around you has intensified dramatically, meaning the air between you and a charged cloud is becoming conductive. This is a life-threatening situation. Act immediately.

The 30-30 Rule: Your Primary Safety Tool

The 30-30 rule is the simplest and most effective guideline for lightning safety. It has two parts, both built around the number 30:

First 30: When you see lightning, count the seconds until you hear thunder. If the count is 30 seconds or less, the storm is within six miles and you should immediately seek shelter.
Second 30: After the last thunder is heard, wait at least 30 minutes before going back outside. Lightning can strike up to 10 miles from the center of a storm, and many lightning fatalities occur after people believe the storm has passed.

The physics behind this rule are straightforward. Sound travels at approximately 343 meters per second, or roughly one mile every five seconds. A 30-second gap between flash and thunder means the lightning struck about six miles away. While that may sound far, lightning bolts regularly extend 10 or more miles from the storm center, meaning a storm six miles out is already within striking range of your location.

If You Are Outdoors

Being caught outdoors during a thunderstorm is the most dangerous lightning scenario. The National Weather Service data shows that the vast majority of lightning fatalities occur to people who were outside when struck. If you are outdoors and a thunderstorm approaches, your priority is to get inside a substantial building or a hard-topped vehicle as quickly as possible.

Seek Proper Shelter

A substantial building means one with plumbing and electrical wiring, which provides a path for lightning to follow to the ground without passing through you. A car with a hard metal roof (not a convertible) is the next best option. The metal shell acts as a Faraday cage, directing the electrical current around the outside of the vehicle and into the ground.

Shelters that do not provide protection include: picnic pavilions, open garages, tents, dugouts, sheds without electrical wiring, bus stops, and rain shelters on golf courses. These structures may keep you dry but offer no meaningful lightning protection.

If No Shelter Is Available

If you are caught in an open area with no building or car within reach, take the following steps:

Move away from high ground. Lightning tends to strike the tallest object in an area. Get to lower terrain if possible, but avoid ravines or ditches that could flood.
Move away from isolated tall objects. Do not shelter under a lone tree. Isolated tall objects attract lightning, and standing near one dramatically increases your risk. Stay at least twice the height of the tree away from it.
Move away from water. Water is an excellent conductor of electricity. Get away from lakes, rivers, pools, and any standing water. Drop fishing rods and other long metal objects.
Separate from groups. If you are with other people, spread out at least 20 feet apart. This reduces the chance that a single strike will injure multiple people and ensures someone is available to call for help.
Assume the lightning crouch. As a last resort, crouch down on the balls of your feet with your feet close together, wrap your arms around your knees, and lower your head. This minimizes your contact with the ground and reduces your profile. Do not lie flat on the ground, as this maximizes your exposure to ground currents from a nearby strike.

If You Are Indoors

Being inside a well-built structure is far safer than being outdoors during a thunderstorm, but indoor lightning injuries do occur. Lightning can enter a building through direct strikes, through wires or pipes that lead outside, or through the ground. Once inside, current can travel through electrical wiring, phone lines, plumbing, and metal frameworks.

Stay away from windows and doors. Open windows and doorways can allow a side flash from a nearby strike to enter the building. Close windows and stay in interior rooms.
Avoid plumbing. Do not shower, bathe, wash dishes, or touch faucets during a thunderstorm. Metal plumbing pipes conduct electricity, and water provides an additional conductive path. This is one of the most commonly overlooked indoor lightning hazards.
Unplug electronics. Lightning-induced power surges can destroy computers, televisions, and appliances even if they are turned off. If a storm is approaching, unplug valuable electronics before the lightning gets close. Surge protectors help but cannot fully protect against a direct or nearby strike.
Avoid corded phones. Corded landline phones are directly connected to outside wiring and can transmit a lightning surge to anyone holding the handset. Cordless phones and cell phones are safe to use during storms.
Stay off concrete floors and walls. Concrete often contains metal rebar or wire mesh that can conduct lightning. Avoid leaning against concrete walls or lying on concrete floors, particularly in garages and basements.

First Aid for Lightning Strike Victims

If someone near you is struck by lightning, immediate action can save their life. Despite a common myth, a person struck by lightning carries no electrical charge and is completely safe to touch. Do not hesitate to provide assistance.

Call 911 immediately. Lightning strikes are medical emergencies. Even if the person appears uninjured, internal damage may be severe.
Check for breathing and pulse. The most common cause of death from lightning is cardiac arrest. If the person is not breathing or has no pulse, begin CPR immediately. Many lightning victims can be resuscitated if CPR is started quickly.
Look for burns. Lightning can cause burns at entry and exit points on the body, as well as along the path the current followed. These burns may appear minor but can indicate deeper tissue damage.
Do not move the person unless there is continued danger from additional lightning strikes. Spinal injuries can occur from the force of the strike or from being thrown.
Treat for shock. Keep the person warm and lying down until emergency services arrive.

The 30-Minute Wait: After the Storm

One of the most dangerous moments in any thunderstorm is when people believe it has ended. Lightning can strike 10 or more miles ahead of or behind the main body of a storm. The trailing edge of a thunderstorm can produce just as many dangerous strikes as the leading edge. The NWS recommends waiting a full 30 minutes after the last observed lightning or thunder before resuming outdoor activities.

This 30-minute rule saves lives. Analysis of lightning fatality data shows that a significant percentage of victims were struck either before the main storm arrived or after it appeared to move away. The temptation to get back to a game, a hike, or a job is strong, but patience is the difference between safety and tragedy.

Stay Informed

The best defense against lightning is awareness. Monitor weather forecasts during thunderstorm season, use real-time lightning tracking tools like our Florida lightning map, and review our comprehensive lightning safety tips guide. When lightning is in the area, there is no safe place outdoors. Get inside, stay inside, and wait it out.

What to Do When Lightning Strikes Nearby