Storm forecasters have predicted that tornadoes may hit Ireland on Thursday.
Heavy rain, severe wind gusts and tornadoes for the country, along with the possibility of an isolated large hail event have been forecast by the European Storm Forecast Experiment (ESTOFEX).
This "level one" threat, which gives a 5% to 15% chance of severe weather conditions, was issued alongside Met Eireann's yellow weather warning.
The country is braced for a battering of flash floods and thunder storms, with up to 50mm of rain expected to fall in parts overnight.
With the worst of the weather expected west of Munster and Connacht, road safety chiefs have warned motorists, cyclists and pedestrians to take extra care in the hazardous conditions.
"The changeable weather that's being forecast for the coming days will present some very challenging road conditions for road users," Mr Brett said.
"As visibility is greatly reduced while travelling in heavy rain remember to allow extra time to complete your journey."
Munster, Connacht and west Ulster are expected to get the worst of the forecasted thunderous downpours and flash floods. Met Eireann warned Leinster, Donegal, Monaghan and Cavan would also be hit by torrential rain.
This comes a week after some areas of Dublin were ravaged by flooding, and landmark department store Clerys was forced to shut its doors for days after parts of its roof fell through.