London Bridge
People reflected in a building glass, walk on the Southbank of the River Thames, with London Bridge on the background, central London. Image Credit: AFP

The unseasonably hot weather across northwest Europe will extend into next week, with London set to exceed 30C (86F) on Wednesday.

Temperatures in Paris are forecast to remain at or above that level for the next seven days, according to Maxar Technologies Inc. The autumnal heat also spans Germany and Scandinavia.

The Northern Hemisphere has faced searing heat from China to California this summer, with July being the world's hottest month on record. Fossil fuel emissions are warming the planet, triggering extreme weather from wildfires in Greece and Canada to violent storms and flooding. By contrast, the UK experienced two months of unseasonably cool weather in July and August.

An active tropical cyclone season "is helping to amplify the pattern across the North Atlantic, and has pushed the jet stream well to the north of the UK, allowing some very warm air to be drawn north," the UK Met Office's Deputy Chief Meteorologist Mark Sidway said in a statement. "It's a marked contrast to the much of meteorological summer, when the UK was on the northern side of the jet stream with cooler air and more unsettled weather."

In southern Europe, last month's extreme heat has given way to heavy rains and thunderstorms. An emergency bulletin for dangerous weather has been issued across Greece, with gale-force winds and the risk of flash floods.

That follows flooding in Spain over the past few days, with heavy rainfall damaging infrastructure and disrupting road and rail transportation.