Temperatures could plummet to -20C (-4F) in parts of the south later, setting new local records.

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The water itself is kept at a comfortable 68F (20C), in an air-conditioned room.

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And forecasters warned they could fall to -20C in the North East and Highlands at the weekend.

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Stored at a dry -20C and robotically-selected, it has the capacity to store 90 million chemical compounds.

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Newquay, in Cornwall, only reached 18C, while Belfast registered 19C and Glasgow 20C.

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He said sheep could cope in temperatures as low as -20C (-4F), and crops were protected from frost by the snow.

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Last night temperatures in England, Wales and Northern Ireland averaged between minus 5C and minus 10C, whilst in Scotland they typically fell to between minus 15C and minus 20C.

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He said temperatures were dropping to -20C in places.

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Groups of infectious donors and recipients then had to spend 15 hours a day together for four days in common rooms, which were kept at 20C (68F), where they were constantly monitored.

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