Information on update: The warning area has been expanded, particularly across northern England, south Wales and southwest England. Very hot weather will continue in general until at least Thursday across the highlighted region, although some variations from place to place and day by day are likely. Temperatures by day are widely expected to exceed 30 Celsius, with the hottest areas potentially peaking around 38-40 Celsius within the embedded red warning. Overnight, temperatures are unlikely to fall much lower than high teens Celsius, and some places will not fall below low 20s Celsius. These high temperatures will also be accompanied by high humidity. Cooler conditions may begin to become established from the west following this period, but confidence is low. For further details see https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings.

After another very hot day, scattered showers and thunderstorms are expected to move towards southwest England during Thursday evening and night. Whilst many areas will miss them, thunderstorms may produce sudden, gusty winds with 50 to 60 mph possible. Frequent lightning, hail and heavy rain are additional hazards. Impacts are slightly more likely towards the south coast of Devon and Cornwall. For further details see https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings.

Forecast weather is likely to cause significant impacts across health and social care services, including:

• a rise in deaths, particularly among those aged 65 and over or with health conditions. We may also see impacts on younger age groups
• a likely increase in demand for health services
• temperatures inside places like hospitals, care homes, and clinics dropping below the levels recommended for assessing health risks
• challenges keeping indoor temperatures at the recommended 18째C leading to more risk to vulnerable people
• staffing issues due to external factors (such as travel delays)
• other sectors starting to observe impacts (such as transport and energy)