Stay safe in thunder and lightning

Thunderstorms can occur at any time of the year and can often pass quickly with minimal impacts. It is during the summer months when thunderstorms in the UK are most likely to produce large hail, gusty winds and torrential downpours that can cause disruption to transport networks and damage property.

One of the most notable aspects of thunderstorms can be the localised nature of the impacts they could bring. In particular, this in particular can be the case with rainfall amounts, with big differences in amounts that fall falling from one place to another and over a very short distance. This can make driving conditions very hazardous. Other hazards include hail, decreased visibility, sudden gusty winds, standing water and of course lightning.

Make sure you know what to do

When we issue a thunderstorm warning, we do this because the impacts can be very severe even if they are also very localised so likely to impact fewer people. It’s worth being aware of what you can do to stay safe if you find yourself in an impacted area.

Before the thunderstorm

• Lightning can cause power surges, unplug any non-essential appliances if not already using a surge protector.
• Seek shelter if possible. When you hear thunder you are already within range of where the next ground flash may occur, lightning can strike as far as 10 miles away from the centre of a storm.

During the thunderstorm

• Telephone lines can conduct electricity so try to avoid using the landline, unless in an emergency
• If outside avoid water and find a low-lying open place that is a safe distance from trees, poles or metal objects
• Avoid activities such as golf, rod fishing or boating on a lake
• Be aware of metal objects that can conduct or attract lightning, including golf clubs, golf buggies, fishing rods, umbrellas, motorbikes, bicycles, wheelchairs, mobility scooters, pushchairs, wire fencing and rails. If you are in a tent, try to stay away from the metal poles
• If you find yourself in an exposed location it may be advisable to squat close to the ground, with hands on knees and with head tucked between them. Try to touch as little of the ground with your body as possible, do not lie down on the ground
• If you feel your hair stand on end, drop to the above position immediately

After the thunderstorm

• Avoid downed power lines or broken cables
• If someone is struck by lightning, they often suffer severe burns. The strike also affects the heart, so check if they have a pulse.

Driving in a thunderstorm

If you are caught out in thunder and lightning it is advised that you wind up the windows and stay inside your car. This is because in the vast majority of cars with a metal roof and frame, the frame will act as a conductive Faraday cage, passing the current around the passengers inside and on to the ground.

• Soft-top convertibles, with their fabric roofs, are the most at risk and could catch fire if struck by lightning
• Be aware that current can travel through other parts of many modern cars, including GPS and radio systems. Cars with metal interior handles, foot pedals and steering wheels can also carry current
• Cars can be damaged both internally and externally by lightning strikes

Thunderstorms can also bring a risk of sudden gusty winds, those most at risk would include cyclists, motorcyclists and high sided vehicles.

• Remember to give vulnerable road users including cyclists, motorcyclists and pedestrians more room than usual. They are more likely to be blown around by side winds – always keep a safe distance.
• Keep your speed down, lowering your speed will lower the distance you travel when buffeted around by the wind.

Hail storms can be extremely dangerous to drive in reducing your ability to see and be seen, as well as causing damage to your vehicle. If hail is severe, stop and pull over to a safe place and remain inside the vehicle