Warning: Yellow

To expect: Thunderstorms

Affected areas: East of England, London and South East England

Start time estimate: Friday 10pm

End time estimate: Saturday 12am

The Met Office has announced a Yellow thunderstorm warning for East of England and London and South East England until early Saturday. All local areas affected are listed below.

A Yellow weather warning is in place from Friday 10pm until Saturday 12am. The forecast suggests the regions concerned can expect to see frequent lightning strikes and heavy rain.

The Yellow alert for thunderstorms was issued at 11:52am on Friday, July 18.

A Met Office forecast said: “Scattered heavy showers and a few thunderstorms will develop later on Friday evening, moving northwards from the English Channel into parts of southeast England. Whilst not all areas will see these during this period, there is scope for rainfall accumulations of 20-30 mm in some places by midnight, perhaps higher in isolated locations. More widespread heavy rain, torrential in places, is anticipated during the early hours of Saturday, covered by a separate warning.”

What to expect

Some flooding of a few homes and businesses possible, leading to some damage to buildings or structures; Probably some damage to a few buildings and structures from lightning strikes; There is a good chance driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus; Delays to train services are possible; Some short term loss of power and other services is likely.

What should you do during intense thunderstorms?

Consider if your location is at risk of flash flooding. If so, consider preparing a flood plan and an emergency flood kit. Give yourself the best chance of avoiding delays by checking road conditions if driving, or bus and train timetables, amending your travel plans if necessary. People cope better with power cuts when they have prepared for them in advance. It’s easy to do; consider gathering torches and batteries, a mobile phone power pack and other essential items. If you find yourself outside and hear thunder, protect yourself by finding a safe enclosed shelter (such as a car). Do not shelter under or near trees, or other structures which may be struck by lightning. If you are on an elevated area move to lower ground. Be prepared for weather warnings to change quickly: when a weather warning is issued, the Met Office recommends staying up to date with the weather forecast in your area. For further details see Met Office Warnings & Advice.

Full list of local regions affected

East of England
Cambridgeshire, Essex, Hertfordshire, Southend-on-Sea, Suffolk, Thurrock

London and South East England
Bracknell Forest, Brighton and Hove, Buckinghamshire, East Sussex, Greater London, Hampshire, Kent, Medway, Portsmouth, Slough, Surrey, West Sussex, Windsor and Maidenhead

What is a yellow weather warning?

The Met Office has three categories of weather warning, depending on the likely impact of severe weather and also how likely it is to strike in a particular area.

A yellow warning is issued when weather conditions are expected to disrupt travel and traffic and may impact on daily routines but are not likely to pose a risk to life or property.

An amber warning is more severe and advises people to think about changing their plans to minimise the risk.

A red warning means weather conditions are expected to be dangerous with widespread damage to property and a risk to life, with the public usually advised to avoid travelling.

The Yellow weather alert for thunderstorms will remain in place until 12am on Saturday.