Flooding , power cuts and train delays could be imminent in west London as weeks of unending sunshine are set to draw to a close.
The Met Office has issued its very first thunderstorm weather warning for the area in its 164-year history.
London has experienced very little rain over the last three weeks, but this looks set to change with rain forecast start on Thursday (July 12).
The yellow weather warning for thunderstorms is in place for Friday (July 13), and is spread across west London as well as a vast area of central and southern England and parts of Wales.
The warning is in force between 11am and 8pm, and could bring up to 20mm of rain in just an hour in some area, the Met Office has warned.
Anyone driving in the capital on Friday should be aware that "there is a good chance driving conditions will at times be affected by spray and standing water", which could lead to delays on your journey.
For those using train services, the Met Office has warned that delays due to the thunderstorms are possible.
The Met Office has also warned of potential flooding to businesses and homes as well as "some short term loss of power and other services due to lightning strikes".
However, forecasters have issued a caveat, saying "as is the nature of showers however, some places within the warning area will miss them altogether, and have a dry day".
Weather warnings for thunderstorms and lightning were only introduced by the Met Office earlier this year, alongside winds, snow, rain, ice and fog.
What to expect in a thunderstorm:
- Spray and sudden flooding could lead to difficult driving conditions and some road closures.
- There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes or hail.
- There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost.
- Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services.
- There is a small chance of fast flowing or deep floodwater causing danger to life.