A Status Orange wind alert has been issued for County Waterford by Met Éireann.
The warning comes into effect from 9 pm Wednesday and remains valid until 6 am Thursday morning.
Cork is to be placed on high alert between 9 pm and midnight tonight with a Status Red weather warning of very severe and damaging winds.
A Status Yellow wind warning for the rest of the South East kicks off at 9 pm tonight and will stay in effect until 23:59 on Thursday.
Met Éireann is warning that gusts could lead to gusts of up to 170 km/h in places:
"Storm Ellen will track over Ireland this evening and tonight bringing severe and damaging winds. Heavy rainfall and storm surge will result in some flooding.
"It will become very windy on Wednesday night and throughout the day on Thursday. Severe gusts are likely and there is a risk of some disruption. Due to the combination of storm surge, spring tides and onshore winds, there is a potential risk of coastal flooding," said Met Éireann.
Carlow Weather's Alan O'Reilly took to Twitter earlier this morning, advising people to take the warnings seriously:
Weather warnings have been updated now by Met Éireann. Please take heed of warnings. Especially near the coasts and if you staying in tents or caravans etc! #StormEllen pic.twitter.com/El9a1FbBzV
— Carlow Weather (@CarlowWeather) August 19, 2020
Image: Storm Ellen as it approaches Ireland, Nullschool.