On Monday, the Met Office, in collaboration with public health partners, issued its first ever extreme heat warning as western areas are expected to see unusually high and prolonged temperatures until the end of the day on Thursday. An amber extreme heat warning has now also been issued for Northern Ireland from Wednesday morning through to midnight on Friday.  

The yellow thunderstorm warning covers central and southeast England, which is set to get the brunt of some thundery downpours of rain as well as lightning. The warning will be in force from 1pm on Tuesday through to midnight. Although many areas will miss the downpours, thunderstorms are likely to develop in the area bringing torrential rain, frequent lightning, large hail and gusty winds. Where the heavy rain does fall could see between 20-30mm of rain within 1-2 hours.  

The yellow warning suggests some quick flooding of homes and businesses is possible and driving conditions are expected to be affected by the surface water. Some disruption is also possible for rail and bus services and power cuts could also occur.  

Met Office Principal Operational Meteorologist Neil Armstrong said, “Although the UK is predominantly very warm and hot at the moment, as is referenced with our extreme heat warning, there is a risk of some locally intense thundery downpours developing across parts of England this afternoon.  These could be torrential in places across central and southeast England bringing a risk of some localised flooding. 

“Although the heavy rain will miss most places, where the rain does fall it will be heavy and bring with it the risk of hail, thunder and lightning. 

“The yellow warning for thunderstorms will be in place until midnight on Tuesday, but there remains a risk of further afternoon thunderstorms through to the end of the week.” 

The Met Office’s first amber extreme heat warning is also currently in force, which covers a large part of Wales, all of southwest England and parts of southern and central England until midnight on Thursday.  

Northern Ireland also now has an amber extreme heat warning running from 8am on Wednesday through to midnight on Friday. Temperatures could reach up to 33C in isolated places.  

The warnings come as the forecast continues to signal for unusually high temperatures for western areas in particular, as well as continuing high nighttime temperatures creating potential impacts for health. The prolonged nature of the current heatwave has also been a factor for the increased impacts from this continued heat.   

The impacts of extreme heat can be many and varied. It can have health consequences, especially for those who are particularly vulnerable, and it can impact infrastructure, including transport and energy, as well as the wider business community. During hot weather there’s often increased traffic near coastal areas, increased use of open water by the public, and an increase in wildfire risk. 

Much of the UK has been in heatwave conditions in recent days, but temperatures are expected to climb further early this week, possibly reaching 33C in some western areas, but widely high 20s and low 30s elsewhere.   

The Extreme Heat Warning coincides with an extension to Public Health England’s Heat Health Alert through to Friday, reflecting the risks to the health sector in England.  

Dr Owen Landeg, Scientific and Technical Lead at PHE, said: “Everybody can be affected by high temperatures and most people are aware of good health advice for coping with hot weather. However, it’s important to keep checking on those who are most vulnerable such as older people and those with heart or lung conditions. 

“As we experience the first hot weather episode of the year, it’s important for everyone to remember to adapt their behaviours. This is particularly important during the pandemic with many people self-isolating. 

“Most of us want to enjoy the sun. Remember to look out for signs of heat exhaustion and follow our simple health advice to beat the heat.” 

Find out how to stay safe in a thunderstorm.  

The Amber Extreme Heat Warning from the Met Office is the first one that has been issued. Find out why we’ve launched an extreme heat warning service.   

Get tips for keeping cool in hot weather with WeatherReady.