Up to 35mm of rain is expected to hit the south coast from Friday 23 November to Saturday 24 November.
The 24-hour status yellow rain warning was issued by Met Éireann with the expectation that Cork and Waterford will be the hardest counties hit.
Long spells of heavy rain are forecast, with accumulations of between 25mm to 35mm of rain.
Coastal regions along the south of the country are expected to experience the heaviest rainfall.
It brings to an end the dry Autumn weather many farmers were enjoying, as Met Éireann report that rainfall in the east and northeast of the country was almost double the norm over the past week.
They also stated that most soils across the country are saturated at this point.
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