People who have left their Christmas shopping to this weekend are in for a shock, with high winds and heavy rain forecast.
Met Eireann has issued a yellow severe weather warn- ing for tomorrow, saying there will be "hazardous conditions".
Richard Guiney, chief executive of retail group Dublin Town, said he expected a 20pc drop in footfall across the city because of the poor weather.
"It's not great timing to have a downpour and strong wind on the second to last Saturday before Christmas," he said.
"This is one of the biggest shopping days of the year for Christmas.
"We expected it to be the busiest Saturday or the second busiest, as we are only two Saturdays away from Christmas.
"We will see footfall down by around 20pc due to the weather.
"We are hoping this picks up on Sunday but we'll just have to wait and see.
"Normally we would see up to around 600,000 to 650,000 shoppers in the city on this day, so it's definitely a shame."
David Fitzsimons, group chief executive of Retail Excellence, said he expected high streets across the country to see a similar picture if the weather is poor tomorrow.
"But shopping centres which have indoor sections and shopping malls won't be impacted too much," he added.
"I still think money will hit the tills later on, perhaps on Sunday and throughout the next two weeks.
"The weather might put a lot of people off on Saturday but there are still plenty of shopping days left until Christmas and it's really important to remind people to shop locally to support local businesses."
Fans attending the Heineken Cup clash between Leinster and Bath at the Aviva Stadium tomorrow are being advised to check Met Eireann's website for weather updates.