Weatherwatch: La Niña strikes out on its forceful voyage round the globe

Unusually cold patches of the Pacific ocean are again on the move, threatening to disrupt weather patterns worldwide

A gigantic blob has surfaced in the Pacific, a monster of unusually cool water stretching out from South America across the equator. This is La Niña and it could send the world’s weather haywire over the next few months. Its impact could even be felt in Britain. Seven years ago one of the most powerful La Niñas on record led to catastrophic floods in Queensland, Colombia, southern Africa, and Pakistan, as well as drought in east Africa and the Amazon. There were record snowfalls followed by spring floods in the US.

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