People holidaying or living on campsites and caravan parks have been warned to seek alternative accommodation as Storm Ellen is set to bring severe and destructive winds.
A red wind warning for Cork has been issued by Met Éireann as the storm sweeps across the country from 9pm tonight.
An orange warning has been issued for Galway, Mayo, Clare, Kerry, Limerick and Waterford.
Heavy rain is also forecast and a storm surge, spring tides and onshore winds may trigger coastal flooding in the coming days.
Head of forecasting at Met Éireann, Evelyn Cusack, said the country has experienced very unseasonable wet and windy weather for the last few days.
"We've upgraded the orange warning for Co Cork to status red for a strong core of severe and damaging winds," she said.
"Generally we expect Storm Ellen to make landfall somewhere off the Kerry/Cork coast at 9pm and then move off either along the west coast or up to the central midlands and on to the north."
Coast Guard head of operations, Gerard O'Flynn, said people should seek shelter if they are staying on a campsite.
"We are appealing to the public not to engage in any form of coastal activity and to be mindful of the risks posed by the extreme tide ranges," he added.
"We're heading towards what we call astronomical high end, low water tide which means we get a very, very high tide and very, very low tide."
He urged the public to stay back, stay high and stay dry.
"We are asking people to stay away from the coast and to stay away from the sea and to avoid the temptation to try and get a fancy photograph or a selfie," he continued.
"It's not the time to take a risk."
Meanwhile, Cork County Council has confirmed that Prior Warning Notices have been put in place at beaches across the county of Cork as there is a high risk that the predicted heavy rainfall and high winds between August 20 and 21 may impact on bathing water quality at these beaches.
The Prior Warning Notices have been placed at the following beaches: Youghal Claycastle, Youghal Front Strand, Garryvoe, Fountainstown, Garrettstown, Coolmain, Warren, Tragumna, Barleycove, Cadogans Strand, Red Strand, Rocky Bay, Oysterhaven, Ballynamona and Ballyrisode beaches.
The council said that these beaches will be sampled Monday August 24 or the next practical available date with results will be available on www.beaches.ie.
The storm is forecast to sweep in from around 9pm on Wednesday, with warnings in place until midday on Thursday.
A spokeswoman for Met Éireann said gale to storm-force winds will travel south east and south west on Wednesday evening and overnight over all Irish coastal waters and the Irish Sea.
"Winds will reach violent storm force 11 for a time on coasts from Carnsore point to Valentia to Slyne Head," the spokeswoman added.
"Unseasonably wet and very windy weather is expected from early Wednesday night until later Friday, with further rainfall and wind warnings likely.
"Strong winds at times may result in unsafe conditions and some disruption, especially over high ground, lakes and sea areas. There is also a risk of flooding."
Minister for Foreign Affairs Simon Coveney said: "Met Éireann have issued a status red severe wind warning for Cork.
"People should take Storm Ellen seriously - if you're in a campsite or caravan park, go home or prepare appropriately.
"Listen to warnings and alerts on media and from local authorities."
The Road Safety Authority has also appealed to road users to exercise caution over the next few days.