The public has been advised not to swim at Front Strand Beach in Balbriggan, north Dublin for the next three days.
Fingal County Council said a "Do not swim" notice has been issued for 72 hours due to a stormwater overflow at Quay Street pumping station on Thursday evening "due to adverse weather conditions".
“A resample is being arranged,” the council said in a statement on Friday afternoon.
“Front Strand Balbriggan remains open but beach users are asked to respect the ‘Do Not Swim’ notices as they have been put in place to ensure that the health of bathers is not compromised.”
The public has been advised not to swim at a number of beaches in Mayo, Donegal and Kerry due to a deterioration in water quality as a result of heavy rainfall in recent days.
Swimming continues to remain prohibited at Merrion Strand in Sandymount as it was deemed to have poor water quality over a number of successive years.
Members of the public can check for water quality at any of the monitored bathing waters in Ireland by accessing the EPA website at www.beaches.ie or by checking the notice board at the entrance to each beach.
A yellow thunderstorm and rain warning is in place for Connacht, Ulster, north Leinster and north Munster until 9am on Saturday.
Met Éireann has warned of "thunderstorm activity" or longer spells of rain with the potential for hail to lead to localised flooding and hazardous driving conditions.
The UK's Met Office has also issued a yellow thunderstorm warning for Antrim, Armagh, Down, Fermanagh, Tyrone and Derry.
Heavy, thundery showers and longer spells of rain will continue throughout Friday, bringing hazardous driving conditions and the ongoing risk of spot flooding.
Occasional drier and brighter spells will occur in the south and southeast this afternoon. Highest temperatures will be between 15 to 19 degrees.
Thundery outbreaks of rain will persist overnight, heaviest and most frequent over the western half of the country.
There will be some drier spells also, particularly over Leinster and Ulster, but with some isolated mist patches.
Further heavy and prolonged showers will occur on Saturday, with longer spells of rain at times, bringing further spot flooding and possible thunderstorms.
There will be occasional drier spells, mainly in the southeast while highest temperatures will be between 15 to 19 degrees in moderate to fresh west to northwest winds.
Met Éireann said there will be further heavy showers on Sunday with a changeable and unsettled picture following into next week.
