UK heatwave - late June to early July 2015

Causes

• High pressure weather system (anticyclone) was sitting over central and southern Europe

• Hot, dry air from the European continent was brought to the UK by air moving clockwise around the anticyclone

• The anticyclone blocked low pressure systems that would normally bring cooler, rainy conditions from the Atlantic Ocean

Consequences

• Temperatures were higher than usual and rainfall was lower than usual

• Train tracks began to buckle causing cancellations across the country

• Temperature hit 36.7°C in Heathrow, the highest temperature on record until July 2022

• 999 calls doubled over the first week of July as people, particularly the elderly, struggled in the heat

• Car breakdown calls we’re up 14% as cars struggled to work

Responses

• Network Rail set speed restrictions on train lines which were vulnerable to buckling to reduce cancellations. This allowed train services to run across the country

• The government issued a Level 3 Heatwave Action Alert. Without this, there could have been many more than the 500 additional deaths

How successful were responses?

Very

• Allowed people to work - economic

• Reduced deaths - social