Extreme heat and outdoor fires

This data analysis was produced for the Fire Committee by the London Assembly Research Unit. The Research Unit provides an impartial, specialist research and analysis service to support the work of the Assembly and inform Londoners.

The analysis was initially undertaken to support the Committee’s meeting on 11 July 2024, to discuss the London Fire Brigade’s (LFB’s) preparedness for dealing with potential fires over the summer period, particularly in light of the experience during the heatwaves of 2022 in London. The LFB is London’s fire and rescue service, overseen by the London Fire Commissioner.

The purpose of the analysis was to understand how many outdoor fires the LFB has been required to attend in recent years, where in London these incidents have occurred, and the relationship to the weather in the city, particularly instances of very high temperatures.

This page displays key data visualisations from the paper. For further information and discussion of data definitions and methodology, please download the full paper.

Monthly fires and average daily high temperatures in London, 2023

Number of outdoor fire incidents by London borough, summer 2022

Summer 2022 was warmer than average and saw intense hot spells in each month. A UK record was set on the 19 July when temperatures reached 40.3°C. The UK also experienced little rain throughout most of July and early August. This combination of intense heat and lower rainfall may have contributed to the sharp increase in outdoor fires seen throughout London.

Outdoor fires by borough, 2020-2023 summer periods

This visualisation shows the number of outdoor fires experienced by London boroughs between 2020 and 2023. A significant increase can be seen across many boroughs in 2022 due to the high temperatures and low rainfall.

Outdoor Fires and Publicly Accessible Green Space

The visualisation shows that between 2020 and 2023, boroughs with more publicly accessible green space generally experienced a higher number of outdoor fires.

Location of and response to incidents during summer 2022 heatwaves in London

The summer of 2022 saw a series of intense heatwaves. This visualisation shows the three periods during which London was covered by a Level 3 Heat Health Alert (HHA). The second heatwave also saw a Level 4 HHA issued from the 16-19 July and a UK record was set when a temperature of 40.3°C was recorded.