Heatwave likely, says Met Office as warm air moves across UK

The Met Office has said that a heatwave is likely across the UK by the weekend, with temperatures in parts of east Wales expected to reach or exceed 30ºC.

Warm conditions will build through the week, starting with temperatures around 27ºC on Wednesday, rising to 29ºC on Thursday. By Saturday, many areas are expected to exceed local heatwave thresholds.

Matthew Lehnert, Chief Meteorologist at the Met Office, said: “An area of high pressure over southern England will build across a larger part of the UK through midweek. Ahead of this, wet and windy weather will affect the far northwest later today and into Tuesday morning. It will remain very warm across parts of the south and east.”

Tony Wisson, Deputy Chief Meteorologist, added: “The rising temperatures this week are a combination of several factors. Settled weather and warm sunshine will allow temperatures to rise day by day. Winds turning more southerly will draw in even warmer air from continental Europe. We could very well see several places exceeding 30ºC, which will be the highest temperatures of the year so far.”

A heatwave in the UK is defined as three consecutive days where the temperature meets or exceeds the threshold for a specific area. In much of the north and west of the UK, including parts of Wales, this is 25ºC. In Greater London and the Home Counties, it is 28ºC.

Mr Wisson said: “By the beginning of the weekend we could very well be meeting heatwave thresholds in places. While the warmest temperatures are likely across London and the east of England, by Saturday heatwave thresholds could be reached across much of the Midlands, low-lying areas bordering the Peak District and even parts of east Wales.”

Forecast temperatures for Deeside are expected to rise steadily this week, with highs of 26°C on Thursday (19 June) and peaking at 27°C on Friday and Saturday.

Warm and sunny conditions are set to continue into Sunday (26°C) before dipping slightly to 24–25°C early next week.

Nights will remain mild, with minimum temperatures around 13–15°C.

No rainfall is forecast, and winds will remain light, reinforcing the likelihood of heatwave conditions developing locally.

Temperatures are expected to fall again early next week as high pressure moves away, though there is uncertainty about how quickly this will happen.

Mr Wisson added: “Temperatures are likely to peak in the low 30s Celsius this weekend before easing sometime early next week. Some forecast models even allow temperatures to rise into the mid 30s Celsius by Monday. While this is feasible, it is considered a lower-likelihood scenario.”