Temperatures are expected to drop to as low as minus four degrees in parts of the country, with a number of status yellow warnings issued.
The first of those comes into effect tonight, and Galway will be under the alert from 6 tomorrow evening.
A status yellow snow and ice warning comes into effect in Donegal from 8pm tonight until 11 tomorrow morning.
The county will be subject to a similar warning again from 6pm tomorrow evening until 11 o'clock on Sunday morning, along with Connacht, Monaghan, Louth and Cavan.
A similar alert has also been issued at the same time on Sunday night into Monday morning.
The rest of the country will be under a low temperature and ice warning from Saturday evening into Sunday morning, and again from Sunday evening into Monday morning.
Met Éireann is forecasting temperatures could fall to between minus two and minus four degrees.
It's warning of hazardous travelling conditions and poor visibility, with a risk of sharp or severe frost.
