11 hours agoLast updated 11 hours ago
This week bears more than a passing resemblance to the last. Cool to start then hot again
Heat wave alerts were issued in several countries as temperatures rose to 40C this weekend.
The storm is travelling slowly up the coast, bringing strong winds and rain to the US state.
In the latest edition of Climate Check, we look at why the polar regions are warming so fast and how higher temperatures there can affect the rest of the world.
Forecasters say temperatures could rise to 50C on Saturday in parts of Utah, Nevada and California.
BBC Weather in association with MeteoGroup
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