Met Éireann has issued a status yellow warning for low temperatures that comes into effect at 6pm.
The forecasters say the low temperatures could lead to difficult travelling conditions, issues for vulnerable people and animal welfare issues.
The warning for severe frost and icy stretches was issued for all counties in the Republic, and will remain in place overnight until 11am on Wednesday morning.
A status yellow warning was also issued for counties in the North, where snow and ice could cause disruption to travel.
