What is causing the unexpected warmth in the UK?

The warm surge is being driven by a strong Iberian jet stream, a fast-moving ribbon of air high in the atmosphere, which experts say is becoming stronger and more frequent due to climate change.

Which regions of the UK will see the highest temperatures?

London, Surrey, Buckinghamshire, and Hampshire are set to see highs near 16°C, with the Isle of Wight possibly reaching 17°C on November 1.

How does the Met Office's forecast for early November look?

The Met Office predicts "above average temperatures" and fewer overnight frosts or fogs than normal, but also warns of "changeable and at times unsettled weather" with low pressure dominating much of the UK.

Home / Weather / Iberian Jet Stream Brings Unexpected Autumn Warmth to UK

Iberian Jet Stream Brings Unexpected Autumn Warmth to UK

27 Oct, 2025

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Summary

Temperatures could reach 17°C in parts of southern England on November 1
Warm surge from Iberian jet stream expected to sweep across Britain
Experts link stronger, more frequent Iberian jet streams to climate change

Iberian Jet Stream Brings Unexpected Autumn Warmth to UK

On October 27, 2025, a weather forecast suggests that the UK is in for an unexpected autumn heatwave. According to the latest data, temperatures could climb to around 17°C in parts of southern England as early as 6am on November 1.

London, Surrey, Buckinghamshire, and Hampshire are all set to see highs near 16°C, with the Isle of Wight possibly reaching 17°C. Other areas such as Kent, Wiltshire, Essex, Suffolk, Northamptonshire, Cambridgeshire, and Lincolnshire may also experience maximum temperatures of around 15°C.

The warmth is being driven by a strong Iberian jet stream, a fast-moving ribbon of air high in the atmosphere that is expected to be in full force by 9am on November 1, sweeping across Europe. While the jet stream is a natural phenomenon, experts say climate change is making these Iberian jet streams stronger and more frequent, leading to extreme weather events like heatwaves and wildfires across the continent.