The United Kingdom is set to enjoy a prolonged period of warm and sunny weather, as an area of high pressure builds from the Atlantic and brings rising temperatures and settled conditions.

The Met Office has given its outlook for the rest of May, and it looks like the heat blast will last for at least three weeks.

When will the heat blast start and end?
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(Photo : ADRIAN DENNIS/AFP via Getty Images)

According to the Met Office, the heat blast will start on Sunday, May 21, and last until at least Saturday, June 10, as per Express.

During this time, many areas of the UK, especially the south, will witness temperatures several degrees higher than average, reaching up to 18°C this week and possibly exceeding 20°C in the following weeks1.

The Met Office spokesman Grahame Madge said: "From the weekend onwards, we have an area of high pressure developing and extending from the Atlantic into southwestern and southern parts, and that will introduce rising temperatures, much more settled conditions.

The heat will build as we've got that high-pressure daily temperature, as long as the high-pressure area continues to reside over us."

What are the criteria for a heatwave?

The Met Office defines a heatwave as an extended period of hot weather relative to the expected conditions of the area at that time of year, as per Mirror.

The criteria vary depending on the region, but generally, a heatwave is triggered when daily maximum temperatures exceed a certain threshold for at least three consecutive days.

For example, in London, a heatwave is declared when the temperature reaches 28°C or higher for three days in a row.

 In contrast, in Glasgow, a heatwave is declared when the temperature reaches 25°C or higher for three days in a row.

The Met Office spokesman said they could see parts of the UK entering heatwave conditions if the above-average temperatures last for three days or more.

Many areas of the UK, especially the south will witness temperatures several degrees higher than average, but these values are likely to be well below the record-breaking temperatures we saw in mid-July.

Also Read: UK Weather Forecast: Strong Winds Likely to Unleash This Week That Could Affect Travel Commutes

How to stay safe and enjoy the heat blast?

While many people may welcome the warm and sunny weather after a cold and wet spring, it is important to stay safe and healthy during a heat blast. The Met Office advises people to follow these tips:

  •  Stay hydrated by drinking plenty of fluids and avoiding alcohol and caffeine
  •  Avoid the sun between 11am and 3pm when it is strongest
  •  Wear light, loose-fitting clothing and a hat and sunglasses
  •  Apply sunscreen with at least SPF 15 and UVA protection
  •  Keep your home cool by closing curtains and windows during the day and opening them at night
  •  Check on older people, young children and pets who may be more vulnerable to heat-related illnesses
  •  Seek medical help if you experience symptoms of heat exhaustion or heatstroke, such as headache, dizziness, nausea, confusion or loss of consciousness

The Met Office also encourages people to enjoy the heat blast responsibly and follow the latest government guidance on social distancing and Covid-19 restrictions.

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