Met Éireann has issued status orange and status yellow rain warnings for some counties on Saturday and early Sunday.
A status orange rain warning has been issued for Cork and Waterford. It will come into effect at 8pm on Saturday, expiring at 5am Sunday morning.
A status yellow rain warning will come into effect earlier on at 5pm today, also expiring at 5am on Sunday.
Counties Carlow, Kilkenny, and Wexford will also be under a status yellow rain warning from 8pm on Saturday until 8am on Sunday.
Met Éireann said those in Cork and Waterford can expect heavy rain and possible thundery downpours during the orange rain warning.
There is a possibility of river flooding, especially in mountainous areas, and people can expect very difficult travelling conditions.
Under status yellow rain warnings, the public can expect spells of heavy rain with the possibility of a few thundery downpours.
There may be localised flooding and difficult travelling conditions.