Soaring temperatures caused by a blast of hot air led the UK to post fresh health warnings through the weekend.

The nation’s Health Security Agency issued an amber alert, the second highest, for parts of the country from Friday, signaling risks for people over 65 and those with pre-existing conditions. Unusually, temperatures over the coming days in London and Berlin are forecast higher than in Madrid and Rome, which will be colder than normal.

The mercury will reach as high as 27.5C (81.5F) in the British and German capitals on Saturday, while Frankfurt will get even hotter, according to Maxar Technologies Inc. Most of northwest Europe will be warmer than normal too, the forecaster said in a daily report.

The first really hot temperatures of the year in Europe represent a fresh challenge for the region’s energy and transport infrastructure, exacerbated by the effects of climate change. The heat will boost demand for cooling, potentially sending short-term energy prices up across the region.

It also brings back memories of summer 2022, when record temperatures damaged roads and sparked fires near London as temperatures surpassed 40C in England.

Moving into next week, temperatures could get even warmer in northern Germany and northwest France, Maxar said.

Meanwhile, the south of England may see some thunderstorms as the high pressure area which has been responsible for the last couple of weeks of settled weather for much of the UK will drift away toward Scandinavia, the UK’s Met Office said. The showers could be a welcome change after a long dry spell.

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