Counties Clare, Cork, Kerry, Waterford, Galway, Wexford and Wicklow will be under the warning from 2pm until 8pm.
A separate Status Yellow wind warning will come into place at 4pm for counties Donegal, Leitrim, Mayo and Sligo, remaining in place until midnight.
Potential impacts during the warning will include wave overtopping, loose objects being displaced, fallen trees and branches, and difficult travelling conditions.
Today will also bring much milder temperatures than the recent cold period, with highs of 10 to 13C. There will be some heavy rain and drizzle at first, giving way to lighter rain later in the morning.
Conditions will turn wet and windy in the afternoon, followed by more heavy showers in the evening.
Winds will continue into tonight though they will ease later on, with a mix of clear spells and showers. Lowest temperatures will be between 5 and 9C.
Moving into next week, Met Éireann has said conditions will be “generally unsettled”, with more rain expected.
There will be widespread showers on Monday with highest temperatures of 7 to 11C.
On Monday night, there will be a mix of clear spells and showers, followed by more rain as cloud builds up in the west. Lowest temperatures will range from 1 to 5C.
Tuesday will start off cloudy with rain in some parts and patches of mist and fog. Conditions will clear up during the morning and early afternoon, bringing a mainly dry and clear day, with highs of 5 to 9C.
Tuesday night will be another cold one and it will be dry with long clear spells, bringing frost and possibly some ice. Lows will range from -2 to 3C.
For the latter part of the coming week, Met Éireann has said the weather will continue to be “changeable” and unsettled.