THE Met Office has issued a yellow thunderstorm warning for areas of Somerset and Devon from 11am until 10pm today (May 9).

The warning says: "Heavy showers and thunderstorms will develop through Tuesday, some becoming slow moving across more southern and eastern parts of England during the afternoon and evening.

"A few places could see 20mm of rain within an hour and possibly 30-40mm in two to three hours hours, along with lightning and hail."

People living in the weather warning zone - which affects most of southern England - have been told to expect:

  • Heavy showers and thunderstorms likely to cause some disruption to travel are to be expected
  • Driving conditions could be affected by spray, standing water and/or hail, leading to longer journey times by car and bus
  • Some flooding of a few homes and businesses is possible, leading to some damage to buildings or structures
  • Probable some damage to a few buildings and structures from lightning strikes
  • Delays to train services are possible 
  • Some short term loss of power and other services is possible.

What should you do to stay safe in thunder and lightning?

Before the thunderstorm, 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 try to avoid using the landline, unless in an emergency.

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.