A status yellow ice warning is currently in place for the whole country.
Met Éireann said icy stretches would take effect from Sunday night into Monday morning.
Hazardous travelling conditions are expected, especially on untreated roads and footpaths. Some patches of freezing fog are also possible.
The yellow ice warning is valid from 6pm on Sunday to 12pm on Monday.
Sunday night was cold with widespread frost and icy stretches. Temperatures fell to between -4 and 1 degrees towards morning, coldest in the north.
Showery outbreaks of rain or sleet continued for a time, most frequent in northern, western and southwestern counties, generally clearing by morning.
Staying dry in most areas today with patches of frost and ice lingering through Monday.
There will be a few showers of sleet, generally along Atlantic coastal areas, with isolated snow flurries also possible. There will also be occasional sunny spells, mainly towards the east.
Highest temperatures of 1 to 4 degrees generally, slightly milder in the southwest, in light and variable breezes.
Cold this morning🥶 with a sharp frost, patches of mist/fog🌫️ & icy stretches❄️ which may linger in places.
Mainly dry with sunny spells🌤️. Showers🌦️ in W Munster will mainly become confined to the SW coast by noon.
Showers in N Ulster, some wintry🌨️
Highs🌡️ of 1 to 4°C pic.twitter.com/74ZuIlsWAG
— Met Éireann (@MetEireann) January 16, 2023
Tonight will see widespread sharp frost with temperatures falling to between 0 and -4 degrees or -5 degrees.
Clear spells with scattered wintry showers. Outbreaks of sleet and snow may affect parts of the west and south too. Some freezing fog will likely form with little wind over land.
There will be some sleet and snow showers in places on Tuesday. Bright or sunny spells too. Afternoon temperatures of just 1 to 4 degrees with light to moderate variable or northerly breezes, fresher near Atlantic coasts.
Lowest temperatures of -2 to -6 degrees overnight with further sleet and snow showers. A sharp to severe frost with icy stretches and lying snow in parts. Some freezing fog patches too.
Wednesday will see sunny spells with scattered wintry showers, mainly in the west and north. Highs of 3 to 6 degrees but feeling very cold in a brisk northerly wind. Temperatures will likely fall below zero again on Wednesday night.