Weather model projections suggest parts of England could experience temperatures close to 30C before the end of May. Forecast maps indicate several counties may record highs above 27C over a five-day period.
The projections, based on data from the GFS weather model, show warmer-than-average conditions developing across much of England and Wales. The Met Office has not declared a heatwave and says temperatures are only expected to become “rather warm” later in the month.
Forecast maps published by WXCHARTS indicate that temperatures could begin climbing significantly from May 24. According to the model data, parts of south-east England may reach 27C on that day, while Yorkshire could see highs of 25C. Wales and parts of Scotland are also expected to experience warmer conditions, with temperatures potentially reaching 23C.
Northern Ireland is forecast to remain cooler throughout the period. The weather maps suggest the warmest conditions will be concentrated across England, particularly in counties stretching from the Midlands to the south-east.
Forecast maps show prolonged spell of warmer conditions
According to the GFS weather model, temperatures above 25C could persist for five consecutive days from May 24 onwards. Maps for May 25 continue to show 27C highs in south-east England, with London expected to experience some of the warmest conditions.
East Anglia may also see temperatures reaching 25C, based on projections for the evening of May 25. The data then points to a slight reduction in temperatures on May 26 and 27, although much of England and Wales is still forecast to remain between 20C and 26C.
By May 28, the forecast maps suggest temperatures could peak at 30C in areas west of London. According to WXCHARTS, nearby parts of the south-east may experience highs of 28C and 29C, while temperatures around 27C could extend as far north as Yorkshire. Scotland may return to low-20C temperatures during the same period, while Wales could reach around 25C. Forecast maps do not show Northern Ireland exceeding 20C.
The projections also indicate that as many as 20 English counties may record temperatures of 27C or above at some point during the five-day spell. These counties include Yorkshire, Nottinghamshire, Lincolnshire, Leicestershire, Warwickshire, Staffordshire and Gloucestershire, alongside several counties in southern England such as Surrey, Sussex, Hampshire and Wiltshire.
Met Office says official heatwave thresholds may still not be met
Despite the high temperatures shown in some forecast models, the Met Office has not confirmed that an official heatwave is expected. According to the agency, a heatwave is only declared when temperatures meet or exceed a specific threshold for three consecutive days.
Those thresholds vary depending on location. In south-east England, where temperatures are generally higher, the threshold is set at 28C. In cooler parts of the UK, the threshold can be as low as 25C.
This means isolated temperatures of 30C would not automatically qualify as a heatwave if the required duration is not met. The Met Office’s forecast covering May 18 to 27 states that temperatures are expected to begin near average before “recovering” later in the period. The forecast adds that conditions could become “rather warm” towards the end of May, particularly in southern parts of the UK. At this stage, the warmer outlook remains based on model projections rather than confirmed forecasts.
