The Met Office has said Storm Agnes is “intensifying quickly” and will hit Britain and Ireland with damaging winds and big stormy seas.
Meteorologist Tom Morgan said: “Storm Agnes is now very much intensifying quickly about 1,000 miles or so away from the south-west of England, in the Atlantic Ocean, and it’s moving quickly north-eastwards towards the UK.”
He said the storm’s main impact will be strong winds and large waves.
Mr Morgan said: “We are likely to potentially see some damaging winds, the possibility of some brief power interruptions, particularly in Irish sea coastal areas.”
“So Northern Ireland, north-west England, west Wales, and south-west Scotland, that’s where we’ll probably see gusts of up to 75mph tomorrow afternoon, tomorrow evening, that’s when the peak of the winds will be and then Storm Agnes will move across Scotland clearing away from Shetland through Thursday morning.”
He added: “In addition to the winds, there’s going to be some large waves as well, so some big stormy seas, and therefore there might well be some coastal flooding where the waves break on to promenades and on to coastal roads.”
The storm will make landfall on the west coast of Ireland and winds will start to pick up for the UK around midday.
He warned of potential disruption to ferry services across the Irish Sea, bridge closures, power cuts and “small amounts” of damage to buildings.
He described Storm Agnes as “more widespread” than the last named storm to hit the UK – Storm Betty – but said it will not produce “significant widespread and long lasting travel disruption”.