Hot weather: How do the new heat-health alerts work?

A new heat-health alert (HHA) service has been launched in England.

The service warns the public when high temperatures could damage their health.

Run by the UK Health Security Agency (UKHSA) and the Met Office, the system issues alerts to members of the public and sends guidance directly to NHS England, the government and other healthcare professionals.

The alerts are categorised according to severity and include:

Last year was the UK's warmest, with Coningsby in Lincolnshire reaching a record 40.3C on 19 July 2022.

The hottest 10 years on record have all taken place in the last two decade, and the Met Office predicts 2023 will be hotter than 2022.

It is hoped the new system will help reduce illness and deaths.

Dr Matt Patterson at the University of Oxford told the BBC: "The HHA is a tool to better communicate upcoming risks to decision-makers in the health service and to allow them to prepare".

"The UK is going to continue to warm as the world continues to burn fossil fuels. We need to update our infrastructure to help people cope with our warming climate," he said.

A report by the independent Committee on Climate Change said that England was not ready for the unavoidable impacts of global warming.

The level of alert is based on Met Office forecasts and data.

There are four levels ranging from green (least severe) to red (most severe):

Green

Green is the normal level, when advice will be given on how people should prepare to respond if temperatures rise.

Yellow

Yellow alerts will be issued during periods of hot weather that are only likely to affect those who are particularly vulnerable, for example, the elderly or those with existing health conditions.

Amber

Amber alerts will be issued in situations that could potentially put the whole population at risk. It would be expected to affect the NHS through increased demand on GPs and ambulances, for example.

Travel disruption would also be likely.

Red

A red alert is the most severe. This will be issued in situations where the hot weather would be a significant risk to life for even the healthy population.

This could also lead to failures of critical national infrastructure, such as power outages or roads and rail lines being closed due to overheating.

If the alert system had been in place when the UK hit 40C in 2022, there would probably have been an alert in this category.

The first yellow and amber heat health alerts of the year have now been issued in England with temperatures expected to hit 30C.

The amber alert - in place from 09:00 BST on Friday 9 June to 09:00 BST on Monday 12 June - covers the following English regions:

A less severe yellow alert, which advises people to check on vulnerable family and friends, is in place for the north of England and London.

You can sign up to receive both heat-health alerts and cold-health alerts on the UKHSA website.