The Saffir-Simpson scale assigns a storm a number between 1 and 5, with "1" being a weak hurricane and "5" the strongest.

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"Staff worked through the night to tackle the problem but unfortunately the sheer scale of the storm caused localised flooding in low lying parts of central Dundee, " he said.

BBC: Promise to act after flood damage

The Outer Banks of North Carolina saw such gains several decades ago after rebuilding from a storm of similar scale.

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