The Met Office has forecast a peak of 31C in London at 3pm on Monday, August 3, with Manchester due to reach 29C and Cardiff 28C as an amber alert warns of hazardous conditions.
The Met Office forecast for Monday says: "Rain affecting much of Scotland on Monday, some heavy. Scattered showers across Northern Ireland and other western areas, though most of England and Wales fine with some hot sunshine. Humid."
Four regions under amber heat alert
The UK Health Security Agency (UKHSA) has issued four amber heat health alerts covering London, the East Midlands, the East of England and the South East. The warnings run from 9am on August 3 to 9am on August 5.
Rising temperatures are expected to place additional strain on health and social care services, increasing the risk to vulnerable people. The UKHSA said there could be an increase in deaths, particularly among those aged 65 and over or with underlying health conditions.
The agency also cautioned that indoor environments could become excessively warm, heightening the danger to vulnerable people living independently in community and care settings. It also highlighted the threat of water-related incidents, including cold-water shock and drowning.
What the amber alert means
The Met Office explained: "An amber alert would represent a situation in which the expected impacts are likely to be felt across the whole health service, with potential for the whole population to be at risk and where other sectors apart from health may also start to observe impacts, indicating that a coordinated response is required."
It added that in some circumstances a National Severe Weather Warning Service (NSWWS) Extreme Heat warning may be issued in conjunction with and aligned to the HHA. "This situation would indicate that significant impacts are expected across multiple sectors."
