Warning: Yellow

To expect: Thunderstorms

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

Start time estimate: Friday 4pm

End time estimate: Saturday 7am

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

A Yellow weather alert is in place from Friday 4pm until Saturday 7am. The forecast suggests the regions concerned will experience frequent lightning strikes and torrential rain.

The Yellow warning for thunderstorms was announced at 11:48am on Wednesday, June 11.

A Met Office forecast said: “Thunderstorms are possible across parts of eastern and southeastern England from Friday afternoon through to the early hours of Saturday. Although many places within the warning area may not see any impacts, torrential downpours could bring 30-50mm of rain, with a risk of even greater accumulations should thunderstorms line up, and with much of the rain perhaps falling in a short space of time, leading to a risk of surface water flooding. Thunderstorms may also bring large hail, gusty winds and frequent lightning to some places which could cause damage and power cuts.”

What to expect

There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds; There is a small chance of fast flowing or deep floodwater causing danger to life; Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services; Spray and sudden flooding could lead to difficult driving conditions and some road closures; There is a small chance that some communities become cut off by flooded roads; There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost.

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. Prepare to protect your property and people from injury. Before gusty winds arrive, check to ensure moveable objects or temporary structures are well secured. Items include; bins, garden furniture, trampolines, tents, gazebos, sheds, and fences. 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, Norfolk, Southend-on-Sea, Suffolk, Thurrock

London and South East England
Brighton and Hove, East Sussex, Greater London, Kent, Medway, Surrey, West Sussex

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 7am on Saturday.