The UK Health Security Agency (UKHSA) has urged households to watch for 14 symptoms as the Met Office issues rare Red and Amber Extreme Heat Warnings, with temperatures expected to exceed 35°C widely and reach up to 40°C in some areas.
Heat Warnings in Effect
The Met Office has issued Amber Extreme Heat Warnings for Monday through Thursday, with a rare Red Extreme Heat Warning now also in place. The red warning covers local authorities across the East Midlands, East of England, London & South East England, South West England, Wales, and the West Midlands from 9am Wednesday to 9pm Thursday. Affected areas are likely to see maximum temperatures in the shade exceed 37°C, possibly rising to 38–40°C.
The UKHSA has also issued Yellow and Amber Heat Health Alerts, highlighting potential health and social care impacts.
Heat Exhaustion Symptoms
UKHSA guidance explains that heat exhaustion occurs when the body overheats and cannot cool down. It does not usually need emergency medical attention if you cool down within 30 minutes. However, if untreated, heat exhaustion can lead to heatstroke. Common symptoms include:
- Tiredness
- Weakness
- Feeling faint
- Headache
- Muscle cramps
- Feeling or being sick
- Heavy sweating
- Intense thirst
Heatstroke: A Medical Emergency
Heatstroke occurs when the body cannot cool down and body temperature becomes dangerously high. Symptoms include:
- Confusion
- Lack of co-ordination
- Fast heartbeat
- Fast breathing or shortness of breath
- Hot skin that is not sweating
- Seizures
"Heatstroke is a medical emergency," the UKHSA warns. "If you think someone has heatstroke you should dial 999 and then try to cool them down."
Temperature Forecast and Impacts
According to the Met Office, temperatures will quickly rise on Monday morning, reaching 34°C in southern parts of England. Tuesday will see highs of 37°C in southern England and 35°C in southeast Wales. The peak of the heatwave is forecast for Wednesday and Thursday, with temperatures expected to climb to 38°C. By Friday, conditions will be less hot, with highs of 33°C across eastern areas.
Overnight temperatures will be very high, with widespread tropical nights (temperature not dropping below 20°C) across southern parts of England, especially in urban areas. Humidity will also be a factor, making the heatwave even more impactful with heat stress a danger to all.
Met Office Deputy Chief Forecaster Tom Crabtree said: "The forecast heatwave is developing into an impactful severe weather event, with record-breaking June temperatures and very high humidity. The combination of heat and humidity will be oppressive and bring impacts across society from public health and infrastructure, to power and water supplies."
The Met Office warning highlights potential health impacts for the wider population, not just those vulnerable to extreme heat. It also warns of potential heat-related issues for transport, energy, and water supply, as well as an increase in potential water safety incidents as more people visit coastal areas, lakes, or rivers.
