Ireland's Met Eireann weather service issued a "status red" warning for the western Irish counties of Galway, Mayo, Clare, Cork and Kerry. It said Ophelia could bring winds of 50 mph (80 kph) and gusts of more than 80 mph (130 kph) Monday, with the potential for structural damage, high seas and flooding.
Britain's Meteorological Office also warned of very windy weather Monday in Northern Ireland, Scotland and northern England.
The U.S. National Hurricane Center said Ophelia strengthened Saturday from a Category 2 to a Category 3 hurricane, with peak winds near 115 mph (185 kph.) The center said it is likely to weaken by the time it hits land on Monday and Tuesday.
By coincidence, Monday is the 30th anniversary of the Great Storm of 1987, which killed almost 20 people in Britain and felled 15 million trees.
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