Met Office issues rare red weather warning for 38C heatwave

Rare red warning

The Met Office has issued a rare red extreme-heat warning for parts of central and southern England and Wales, with temperatures forecast to reach as high as 38C on Wednesday and Thursday.

The forecaster said the conditions could cause serious illness and danger to life. It also warned that the impacts would not be limited to people already classed as vulnerable.

The warning is the highest level used by the Met Office. It is only the second red warning it has issued for extreme heat, and the first to include Wales.

How the alert developed

The red warning follows a run-up of earlier heat alerts as the forecast intensified.

On June 19, the Met Office issued an amber extreme-heat warning for parts of England and Wales.

By June 21, The Guardian reported that temperatures could climb to 38C between Monday and Thursday, with a 25% chance of exceeding 40C and UK Health Security Agency heat health alerts also in place.

On June 22, the Met Office escalated the situation to red for the areas judged to face the greatest danger as the hottest period approached.

The last red extreme-heat warning came in July 2022, when temperatures reached 40C.

What the Met Office is warning about

The red warning is not just about the temperature itself. The Met Office said the heat could disrupt water, electricity, gas and mobile-phone services.

It also warned of likely disruption on roads, rail and air routes.

The forecaster said substantial changes in working practices and daily routines would be needed in the affected areas.

The warning covers central and southern England and Wales, with the hottest conditions expected on Wednesday and Thursday.

Public health risk

The Met Office said the heat could present a risk of serious illness or death, including for people who might not normally consider themselves vulnerable.

Officials are also warning about the strain hot weather can place on day-to-day life, especially when temperatures stay high overnight and people do not get a chance to recover.

The UK Health Security Agency has heat health alerts in place, adding to the public-health response around the heatwave.

Safety advice and what to watch next

The Met Office advised people to drink fluids, stay out of the sun, avoid exercise in the hottest part of the day and take care around cold water when swimming.

The cold-water warning matters because warm weather often sends more people to rivers, lakes and coasts, where sudden immersion can be dangerous.

Attention now turns to whether the red area is widened or shortened before Wednesday, and whether temperatures in some places go beyond the forecast 38C.

Forecasters are also watching for any June temperature records and for any readings that get close to, or above, 40C.