Met Éireann has warned of a “whole day” weather event from just before dawn on Wednesday and extended its status orange wind warning to a further five counties.
Storm Agnes will hit the south hardest with wind warnings now covering counties Carlow, Kilkenny, Wexford, Wicklow, Cork, Kerry, Tipperary and Waterford. A status orange rain warning remains in place for Kerry, Cork and Waterford.
The conditions will spread throughout the country bringing concerns of falling trees, power outages and flooding, particularly in coastal areas with high seas.
While rain had been forecast to be the worst aspect of the storm, on Tuesday night Met Éireann upgraded its wind warning to cover a total of eight counties.
The southern counties are expected to experience the worst of the rain and wind, beginning in southwest Kerry at about 6am and spreading.
However, with the worst of the wind not coinciding with high tides, that should bring some reprieve to Cork City which must often deal with bad flooding in storm conditions.
“[The wind] will probably cause some coastal flooding, some difficult travelling conditions and possibly power outages with fallen trees, especially given the time of year where the trees are still in quite a bit of leaf,” said Met Éireann meteorologist Brandon Creagh.
“We get these kind of weather systems any time of the year. It’s just when they reach the numerical values of status orange they can do a bit more damage than they would in winter when they are more common due to the trees still being in leaf.”
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Conditions will hit the rest of Munster and Leinster as well, with storm force warnings in coastal areas along the south and east. However, forecasters do not believe Storm Agnes will be upgraded to a red warning status.
The wind will be worst in the afternoon time but rain will begin early and accumulate throughout the day, turning particularly heavy at about 10 or 11am.
“But it’s going to be persistent for the whole day and it’s going to be a whole day event really as the [storm] makes it’s way to Scotland by say midnight tomorrow,” Mr Creagh said.
The status orange rain and wind warnings for Cork, Kerry and Waterford is in effect from 9am to 3pm. Less severe yellow status warnings for Munster and Leinster cover 7am to midnight, illustrating the day long nature of Storm Agnes’s impact.
The UK Met Office has also issued a yellow wind warning for Northern Ireland from 12pm on Wednesday until 7am on Thursday.
The Road Safety Authority (RSA) issued its standard heavy weather appeal, urging road users to exercise caution during the storm. Motorists have been advised to reduce speed and increase breaking distances, as well as being weary of travelling behind heavy goods vehicles that generate high volumes of water spray.