(Bloomberg) -- Europe is set to get its first taste of winter, with a sudden cold snap testing the region’s energy systems.

Temperatures will drop over the weekend, and cities including London and Paris may be 5C to 6C cooler than normal by Monday, forecaster Maxar Technologies Inc. said in a note.

The wintry weather follows a prolonged period of unusually warm conditions in northwest Europe, which has delayed the heating season. While energy bills remain elevated amid the fallout from Russia’s invasion of Ukraine, the region on the whole is much better prepared for peak demand than a year ago.

Storage sites have almost topped out and several countries have added liquefied natural gas terminals over the year — with more yet to come — to offset the drop in piped flows from Russia. Yet supply risks persist, from security threats against infrastructure to rising tensions in the Middle East.

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In Britain, the weather will turn “much cooler” by the weekend, with daytime temperatures as much as 10C lower than early this week across southern England, the Met Office forecaster said in a note. Central and northern areas are likely to see their first overnight frosts of the season.

While the cold snap is expected to ease by the end of next week, temperatures are seen remaining slightly below seasonal norms through much of the month.

For the European winter as a whole, there’s an increasing likelihood of significantly warmer weather than usual, potentially reducing demand for heating fuels and blunting any supply shocks, according to data from the Copernicus Climate Change Service.

--With assistance from Elena Mazneva.

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