The warning comes into effect from 11am.
Warnings for heavy rain have been issued for 13 counties.
A status orange alert will be in place in Dublin, Wicklow and Wexford from 2pm tomorrow until 11am on Saturday.
Before that, a status yellow alert comes into effect for 24-hours from 9am in Cork, Kerry, Limerick, Tipperary and Waterford.
A similar warning will be in place for counties Carlow, Dublin, Kildare, Kilkenny, Louth, Meath, Wexford and Wicklow from 11 o'clock tomorrow morning.
Alan O'Reilly from Carlow Weather, says there will be significant flooding and hazardous travelling conditions, especially in the counties under the orange alert.

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