UK summer forecast 2026

August is expected to be the warmest and driest of the three months, but overall a mixed season is forecast with rain totals close to or slightly below the norm being more likely than above it.

Thundery outbreaks may occur relatively frequently compared to the average, and significant regional variations are expected, with the south and east generally favoured for the warmest and driest conditions.

Over the three-month period, the forecast is for the Central England Temperature (CET) to be 0.25°C to 1.25°C above the average. Precipitation levels of between 85% and 105% are suggested.

The 35.1°C recorded at Kew Gardens, London could turn out to be the hottest day of the year. In the last decade it beats the highest values recorded in 2024, 2023, 2021, 2017 and 2016.

How is the forecast produced?

Factors considered include the following:

• A number of long range computer models run by the global forecasting centres
• Recent climatology and trends during recent seasons
• Teleconnections (such as ENSO)
• Sea Surface Temperatures
• Pattern matching or analogues from previous years

Forecast accuracy

Long range forecasts for the UK and north western Europe continue to display a low skill, in other words they are often inaccurate. This in large part is because the edge of the European landmass is affected by different, competing air masses which can make even short range forecasting very difficult.

Summer month by month

The June headline is for above average temperatures and rain amounts to be close to the average, though starting out unsettled.

July is forecast to bring slightly above average temperatures and rainfall amounts, with an increased risk of heavy showers and thunderstorms.

August temperatures are expected to be above the average, with below normal amounts of rain and a good deal of fine weather favoured.

Read the seasonal forecast in full.