Large swathes of the United Kingdom are expected to enter drought status this week as a fifth heatwave of the year develops, with no significant rainfall forecast. Temperatures are predicted to climb, potentially reaching 35C (95F) by mid-next week, exacerbating already bone-dry conditions across many regions.

The UK Health Security Agency has issued yellow heat health alerts for most of England, warning of potential impacts on health and social care services, as well as an increased risk to vulnerable individuals. These alerts are in place until Tuesday evening and are likely to be updated as the heatwave intensifies.

The Environment Agency (EA) has indicated that several areas in England could officially be declared as being in drought. This comes as public water supplies face increasing pressure due to persistent dry weather and high demand. Reservoir levels across England are predominantly below normal, with five designated as 'exceptionally low'.

This developing situation means that by the middle of next week, temperatures could reach 35C in parts of south-east England. If this occurs, it would mark the fourth consecutive month with temperatures hitting at least 35C. The threshold for an official heatwave is likely to be met across much of England and Wales, signifying the fifth such event for many.

For seven consecutive weeks, less than 10mm of rain has fallen across the country. East and south-east England have experienced particularly severe dryness, receiving less than 1mm of rain in the latest reporting period. Over half of England and the entirety of Wales are already under drought conditions.

Specific areas are experiencing extreme dryness, with Wisley in Surrey reporting over 50 days without any rainfall. Southern England is approaching two months of negligible precipitation. Reflecting the ongoing water scarcity, South West Water recently implemented a hosepipe ban, joining other water companies. In total, more than 20 million people in the UK now live in areas with usage restrictions due to prolonged dry weather, heatwaves, and elevated water demand.

The forecast suggests Sunday will be warmer with temperatures in the mid to high twenties Celsius across many areas, reaching up to 33C in south-east England. While Monday is expected to be cooler, temperatures will rise again from Tuesday across the UK. Scotland and Northern Ireland will see typical temperatures in the low to mid-twenties, while England and Wales will experience mid to high twenties, exceeding 30C in several eastern and southern regions.

Experts note that the persistence of high temperatures and lack of rain are key factors driving the expansion of drought conditions. The cumulative effect of multiple heatwaves and consistently low rainfall is straining water resources, prompting concerns about the long-term impact on the environment and public services.