A status yellow rain warning is in place for the entire country as Met Éireann is warning of possible thunderstorms.
Meanwhile, a status orange rain warning is in place for Cork, Kerry and Waterford.
The alert for Kerry is set to expire at 3pm this afternoon, while it has been extended until 3am tomorrow for Cork and Waterford.
The yellow warning for the rest of country came into effect at 3am this morning and will remain in place until 3am on Monday.
Speaking to Newstalk, Carlow Weather's Alan O'Reilly says the heavy rainfall will cause localised flooding.
"Up to 40 to 50 millimetres of rain is possible in a 24-hour period for Cork, Kerry and Waterford which could lead to spot flooding."
He said people in those counties should take extra care while on the roads.
Rain becoming widespread for a time today 🌧️
Persistent in most areas with some heavy falls & possible thunder ☔️
Localised flooding possible, especially in the south ⚠️
Some dry spells later in parts 🌥️
Humid & breezy. Highs: 16-21°C 🌡️
More here 👇https://t.co/9gKN6SVW9C pic.twitter.com/TAV4KyrQUv— Met Éireann (@MetEireann) September 11, 2022
Met Éireann said for the rest of the day thundery downpours are possible along with localised flooding, especially in the south.
Some drier intervals will develop through the afternoon and evening mostly in the southwest and midlands. Humid and breezy too with highest temperatures of 16 to 21 degrees in moderate to fresh southerly winds.
Monday morning will be cloudy with outbreaks of rain in parts. Sunny weather will develop over the northern half of the country in the early afternoon.
Remaining cloudier further south with patchy rain lingering, but becoming mainly dry and bright in the evening.
Highest temperatures will range from 18 to 21 degrees in the south and southeast but turning much fresher elsewhere with highs of 15 to 18 degrees in moderate northerly breezes..
The national forecaster said Tuesday looks set to be a mainly dry with long spells of sunshine. Fresher than recent days with highest temperatures ranging from 15 to 19 degrees, warmest in south in moderate northerly winds.
It is expected to be a dry day with a mix of cloud and some good sunny spells on Wednesday. Highest temperatures of 15 to 19 degrees in light northerly breezes.
