What is an extreme heat warning? Met Office issues first ever amber warning for high temperatures

The Met Office has today (19 July) issued its first ever “amber warning” for extreme heat, warning of high temperatures for parts of the nation

People enjoy the weather on Bournemouth beach in Dorset (Photos: Met Office / PA)

Temperatures are expected to reach 33C in some western areas of the UK later this week, with high 20s and low 30s expected elsewhere.

What is an extreme heat warning?

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The warning – which is similar to those issued when heavy rain or snow is forecast – covers a large part of Wales, all of south-west England and parts of southern and central England, and will remain in force until the end of Thursday.

It says that “high temperatures both by day and night will continue this week leading to public health impacts”.

The Met Office warning then lists the following impacts:

Adverse health effects are likely to be experienced by those vulnerable to extreme heat
The wider population are likely to experience some adverse health effects including sunburn or heat exhaustion (dehydration, nausea, fatigue) and other heat related illnesses
More people are likely to visit coastal areas, lakes and rivers leading to an increased risk of water safety incidents
Some changes in working practices and daily routines likely to be required
An increased chance that some heat-sensitive systems and equipment may fail, leading to power cuts and the loss of other services to some homes and businesses
Some delays to road, rail and air travel are possible, with potential for welfare issues for those who experience prolonged delays

The warning covers the period from today until Thursday (22 July).

What’s been said?

The Met Office said last month that it would launch weather warnings for extreme heat after a record-breaking number of heatwave deaths were recorded in England last summer.

Chief operational meteorologist at the Met Office, Steven Ramsdale, said: “The high temperatures are going to continue through a large part of this week. Many areas will continue to reach heatwave thresholds but the amber extreme heat warning focuses on western areas where the most unusually high temperatures are likely to persist.

“There’s a continuing risk of isolated thundery downpours late in the afternoons but most areas will stay dry until later in the week. Temperatures should begin to fall for most areas heading into the weekend, with some more unsettled conditions looking to develop.”