UK to Reach 30°C Over Bank Holiday

Temperatures across the UK are forecast to reach 30°C over the bank holiday weekend, with a large, stable block of high pressure settling over western Europe. Professor Hannah Cloke, Regius Professor of Meteorology and Climate at the University of Reading, explains the cause of the extreme heat.

A large, stable block of high pressure is settling over western Europe, and it is this that is the primary driver of what we are about to experience. As air sinks beneath it, it heats up through compression, pushing surface temperatures well beyond what we would expect at this time of year.

This is then further intensified by very warm air being drawn in from north Africa and the Iberian Peninsula, as well as strong solar heating as we approach the longest days of the year.

For parts of south-east England, we could be looking at 30°C, a threshold rarely crossed in May. While daytime temperatures will be exceptional, nights are likely to stay cooler, giving some crucial respite for people who are particularly vulnerable to heat. Professor Cloke notes that farmers are likely to be concerned, as a prolonged spell of heat and dry weather at this stage of the growing season can cause stress, reduce yields and in some cases cause irreversible damage.

Dr Jess Neumann, associate professor of hydrology at the University of Reading, warns that hot weather should not be underestimated, with over 1000 excess heat-related deaths in the UK last year. People are urged to take care during hot weather by staying hydrated, carrying spare water on journeys, wearing adequate sun protection and seeking shade or cool spaces.

Data from the Reading University Atmospheric Observatory shows that 30°C has been reached only 8 times in May in Reading since 1908, with the most recent occurrence in 1953. The earliest ’30’ on University records was 22 May, in 1922, and Reading’s hottest May day to date was 31.9°C, on 29 May 1944.

Source: University of Reading