Storm Agnes is due to make landfall in Ireland on Wednesday morning.
A Status Orange rain warning will be in place for Cork and Kerry from 9am.
Met Éireann is forecasting spells of heavy and occasionally intense rain, combined with very strong and gusty winds.
Potential impacts will include difficult travel conditions, localised flooding and poor visibility.
A Status Yellow wind warning is being issued for Leinster and Munster from 7am.
It will become very windy on Wednesday with very strong and gusty southerly winds, veering westerly later on.
This could lead to coastal flooding, power outages and some fallen trees.
And a Status Yellow rain warning will also be in place for Carlow, Dublin, Kilkenny, Wexford, Wicklow, Cork, Kerry and Waterford from 7am.
Heavy rain is forecast in these areas.
There will also be marine warnings on every coast, ranging from Yellow to Orange.
Storm Agnes will track northwards over Ireland on Wednesday with disruption likely in places.
It will be wet and very windy with outbreaks of heavy rain extending nationwide with the likelihood of some spot flooding.
It will be extremely windy or stormy for a time in the east and south, with the potential for severe and damaging gusts.
Strong onshore winds and high seas will bring the risk of coastal flooding on eastern and southern coasts.
Storm Agnes will clear away towards Scotland on Wednesday night, but it will remain rather unsettled for the remainder of the week.
There is also a wind warning in place for Northern Ireland from midday on Wednesday.