Calderdale is being warned to brace itself for thunderstorms after the Met Office issued a yellow weather warning.
The warning period for the severe weather is between 1pm and 9pm today (Wednesday).
A spokesperson for the Met Office said: "Although not everywhere will get one, heavy showers and thunderstorms are expected to break out across central and northern England during Wednesday afternoon, easing from the south during the evening.
"These thunderstorms bring the potential for lightning strikes and hail, with sudden downpours and gusty winds."
The thunderstorms may bring some temporary disruption to travel and power supplies.
What to expect from the possible thunderstorms
Possible damage to a few buildings and structures from lightning strikes. Some short term loss of power and other services is likely, with possible delays to train services.
There is a good chance that driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus.
Flooding of a few homes and businesses is possible.
How to stay safe in thunderstorms
Thunderstorms can occur at any time of the year but 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.
This, in particular, can be the case with rainfall amounts, with big differences in amounts that fall 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.
Before the thunderstorm
- Unplug all non-essential appliances, including the television, as lightning can cause power surges.
- 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
- Avoid using the phone - telephone lines can conduct electricity
- Avoid using taps and sinks - metal pipes can conduct electricity
- 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.