Temperatures are set to pick up in the UK from the end of May, but what temperature does it need to reach to count as an official heatwave?

Thursday (May 26) is anticipated to be the hottest day of the year so far, the Met Office has predicted.

Temperatures could be as high as 25C on that day in parts of the UK, with south-east Wales and the West Midlands area of England set to see the best of the weather.

An onshore breeze will keep temperatures in the South East of England cooler, but dry, bright weather is still expected across the area and most of the country for the rest of the week.

Glasgow Times: The different thresholds for a heatwave depend on where you are in the UKThe different thresholds for a heatwave depend on where you are in the UK (Image: PA)

Here's what the temperature would need to get to in various parts of the UK in order for the Met Office to record it as a heatwave.

What counts as an official heatwave in the UK?

On the Met Office website, it states: "A UK heatwave threshold is met when a location records a period of at least three consecutive days with daily maximum temperatures meeting or exceeding the heatwave temperature threshold."

This threshold varies by county, so, for example, London, Surrey, Berkshire, Bedfordshire, Buckinghamshire, Hertfordshire and Cambridgeshire need to have a temperature of 28C or more for three days for it to count as a heatwave.

Meanwhile, Kent, Sussex, Hampshire, Wiltshire, Essex, Norfolk, Suffolk, Oxfordshire, Gloucestershire, Worcestershire, Warwickshire, Northamptonshire, Lincolnshire, Rutland, West Midlands, Leicestershire and Nottinghamshire require three days of 27C or more.

Counties that need 26C or more for three days include the Isle of Wight, Dorset, Somerset, Herefordshire, Shropshire, Staffordshire, Cheshire, Derbyshire, South Yorkshire, and the south-east of Wales.

Everywhere else in the UK needs the temperature to reach 25C or higher for three days.

The Met Office adds: "The geographical differences reflect the differences in climate across the UK.

"The threshold temperatures have been calculated using the 1991-2020 climatology of daily maximum temperature at the mid-point of the meteorological summer (15 July)."