Heatwave Conditions in London and Southern England

The UK experienced its hottest day of the year as temperatures soared to 32°C (90°F) at both Heathrow and Kew Gardens in southwest London, surpassing the previous high of 31.9°C recorded in central London on 19 July. The Met Office anticipates that London, southern England, and southeastern Wales will meet the official criteria for a heatwave this week.

Brief Heatwave with Thunderstorms Expected

However, the intense heat may be short-lived. The Met Office has issued a yellow alert for thunderstorms across large parts of England and Wales later in the week.

Yellow Heat Health Alert Issued

The UK Health Security Agency (UKHSA) has issued a Yellow Heat Health Alert for all areas of England except the North East and North West. This alert, the second of four tiers, indicates that the heat is "unlikely to impact most people" but could affect the elderly and vulnerable. The UKHSA warns that the hot spell may lead to an "observed increase in mortality," particularly among those aged 65 and older or individuals with preexisting health conditions. Younger age groups may also be affected.

Children cool off by running through a sprinkler in London's Parliament Square amidst the soaring temperatures.

The UKHSA also cautions about increased demand for remote healthcare services and the risk of excessively high internal temperatures in hospitals and care homes, potentially complicating clinical risk assessments.

Above-Average Temperatures

Many regions are experiencing temperatures four to five degrees warmer than the July average, according to BBC Weather. In Wales, the year's highest temperature was recorded at 29°C in Usk, near Newport. Scotland and Northern Ireland, however, did not see record-setting temperatures, with highs of 22.3°C and 23°C respectively on Tuesday.

Heatwave Criteria and Forecast

The Met Office defines a heatwave in the UK as a period of at least three consecutive days with daily maximum temperatures meeting or exceeding specific thresholds. For London and the surrounding areas, the threshold is 28°C, which has been exceeded since Monday. Temperatures are expected to remain above this level through Friday.

In southeast England, the threshold is 27°C, and in other parts of southern England and the Midlands, it is 26°C. According to Met Office meteorologist Becky Mitchell, much of southern UK is "entering a heatwave" based on current forecasts, although it has not yet been officially recorded.

Scotland, Northern Ireland, Wales, and most of northern and western England have a heatwave threshold of 25°C. If temperatures in Scotland do not reach 25°C on Tuesday, it will be the first July since 2010 that this level has not been attained. Photo by Alisdare Hickson, Wikimedia commons.