A status yellow warning for thunderstorms has been issued by Met Éireann for all counties in the Republic.
The warning will come into effect at 3pm on Sunday and will stay in place for 12 hours.
Met Éireann says that while some places will stay dry, hit-and-miss thunderstorm activity along with hail and heavy downpours may lead to spot flooding and hazardous driving conditions.
The warning will coincide with another warning for high temperatures which will remain in place until 6am on Monday morning.
Temperatures are expected to reach 30 degrees in parts of Galway today and tomorrow.