A status orange thunder warning has been issued for 16 counties.
Met Éireann issued the alert for Cavan, Monaghan, Donegal, Dublin, Carlow, Kilkenny, Laois, Longford, Wexford, Wicklow, Westmeath, Leitrim, Roscommon, Sligo, Cork, Tipperary until 10 o'clock tonight.
The warning says there will be severe thunderstorm activity in the affected areas over the next few hours.
Torrential downpours and lightning strikes are also likely.
Latest lightning data (4pm).
Crosses represent lightning strikes.
White = in the last 20 minuteshttps://t.co/YT10HK8tIi pic.twitter.com/PtoLzibHCM— Met Éireann (@MetEireann) June 1, 2018
It comes amid a separate status yellow warning for most areas of the country, with flash flooding possible.
Met Éireann says it's difficult to pinpoint where will be worst affected but are asking motorists to heed the yellow warning as there will be reduced visibility during showers.
A yellow rainfall warning is in place across most of the country until 10 o'clock tonight with the exception of west Connaught which is likely to avoid the heavy showers.
Rainfall Warning Update
Status: Yellow
Location: All areas bar the west coast
Valid: Friday 11am to Friday 10pm
High intensity rainfall in scattered thunderstorms leading to spot flooding. Between 25 and 50 mm of rainfall possible locally in short periods.https://t.co/b24grJkqcb pic.twitter.com/Kh0Dj12hqk— Met Éireann (@MetEireann) June 1, 2018
Between 25 and 50 mm of rainfall expected in short showers but the severity, frequency and exact location of the downpours is quite unpredictable.
Gerry Murphy is a forecaster and meteorologist with Met Eireann, says 50 milimetres is unlikely to happen in one shower,
"What would be more likely to happen is that in a particular place where the showers are streaming up towards it over a few hours you could get a manse of that magnitude where the heavy or thundery showers occur. But it's difficult to pinpoint exact locations."
The heavy showers can reduce visibility for drivers while flash flooding can also create hazardous driving conditions.
The scattered rainfall is likely to stay away from west connaght but will hit most other areas,
"Parts of Ulster, Leinster, Munster and East Connaught. It does look as if Western coastal counties will escape the worst of the showers but for much of the country, the midland central and eastern parts of the country - they'll get the heaviest downpours."
