Scorching temperatures are blanketing parts of Germany and Italy this week, prompting heat warnings and straining the region’s energy and transport systems.

Germany’s national forecaster warned of “extreme heat stress on the Upper Rhine” from late morning on Tuesday. A similar alert was issued by the Italian weather service, with the mercury in Sardinia exceeding 40C (104F). The freezing level in the Alps will climb to about 4,600 to 4,800 meters (15,744 feet) on Tuesday, close to the altitude of Mont Blanc, western Europe’s highest mountain.

Europe broke heat records in 2022, intensifying the energy crisis triggered by Russia’s invasion of Ukraine. Temperatures are soaring again this year, with parts of the region, including the UK, witnessing their hottest June on record.

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Summer heat and sinking water levels on the Rhine river, critical for the transportation of energy commodities in Europe, remain in focus this month. The marker at Kaub — a key waypoint on the river west of Frankfurt — is expected to drop below 1 meter on Wednesday, according to Germany’s Federal Waterways Administration.

Last August, the water marker at Kaub fell below 40 centimeters, a level at which many barges found it uneconomical to transit goods. That’s not the actual depth of the water, but rather a measure of navigability.

Forecaster Maxar Technologies Inc. expects Germany’s heat wave to ease by next week, after temperatures in Frankfurt reach 35.5C on Tuesday and 34.5C on Saturday — the peaks of its current 10-day forecast. Still, above-normal temperatures are expected to persist across much of southern Europe, with the Balkans experiencing heat in the low 40s, according to Maxar.

By contrast, the UK and the Nordics will enjoy cooler weather through the next 10 days. London will be 4.2C below the norm on Sunday and Monday.

--With assistance from Angela Cullen.