Scattered thunderstorms are forecast in Dublin, Louth and the western half of Meath on Friday.
Met Éireann has issued a status yellow thunderstorm warning for the three areas, with the warning valid until 3pm.
The forecast for the weekend shows unsettled weather, with a mix of sunny spells and scattered showers hitting the country on Saturday.
On Saturday evening, showers will merge to give longer spells of rain in parts of Connacht, Ulster and north Leinster. Maximum temperatures will reach 19°C in parts.
Scattered showers are forecast on Sunday again, but most frequent in Ulster and Connacht.
It will become cloudy in the southwest during the evening time, with the odd patch of light rain or drizzle possible along the southwest coast, Met Éireann said.
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