The cold snap is set to intensify, with wet snow and sleet forecast to hit the country on Thursday night.
Met Éireann has said Ireland can expect a period of wet snow and sleet tonight, before damp and breezy conditions push in from the Atlantic.
Overnight temperatures will be between 0 and 2 degrees Celsius.
Meanwhile, Thursday afternoon will see highs of 4 to 7 degrees, as sunny spells gradually give way to clouds.
The weather is set to remain cold through Friday and the weekend, with frost and a high risk of icy patches overnight. Showers are also forecast, particularly in western counties, with a risk of hail showers on Friday night.
Temperatures will remain below normal in the coming days, and could dip as low as –1 on Friday and Saturday and –3 degrees on Sunday.
Matthew Martin, meteorologist with Met Éireann, said the weather over the next seven days will see frost at night and temperatures dropping below zero. Next Tuesday is set to see the worst of the wintry showers in the coming days, he said.
“It is the back end of next week where there is a risk of really cold weather,” he said. There was a cold north-west polar flow coming towards Ireland, Mr Martin said.
However, he cautioned the path and impact of the weather system was still “very uncertain” this far out.
