A weather warning for snow on high ground is in place as daytime temperatures fall on Wednesday.
Met Éireann issued the yellow warning – the mildest of three weather warnings – for localised danger from snow, particularly in the Wicklow hills.
Significant falls of snow are expected on high ground, but this is expected to turn to sleet and rain, especially on lower and coastal areas, by nightfall.
Met Éireann has also issued a status yellow weather warning for all six counties of Northern Ireland with heavy rain forecast and hill snow leading to some disruption on Wednesday.
Meteorologist Linda Hughes said one of the most noticeable changes on Wednesday will be a drop in temperature.
The country had been enjoying a mild air mass in recent days, she said, adding that “it will stay cold through most of the week and weekend”.
Met Éireann has also issued an advisory – a lesser notice than a warning – for temperatures turning colder from Wednesday with weather conditions becoming increasingly wintry for the rest of the week. There is a risk of frost and icy conditions, with falls of sleet or snow at times.
Meanwhile, Irish Water has asked home and business owners to check for leaks and to conserve water where possible in advance of expected freezing night time temperatures in the coming days.
The utility said freezing temperatures earlier this month and the subsequent thaw had resulted in higher than normal volume of burst pipes in the public water network.
While the national forecast is for heavy rain with afternoon temperatures of 3 to 6 degrees temperatures are expected to fall to -1 degrees with frost and icy patches in many areas on Wednesday night.
Thursday will be cold with sunny spells and scattered showers, some of hail and some wintry on high ground. Parts of the east will stay mainly dry. Highest daytime temperatures of 4 to 7 degrees with moderate to fresh west to northwest breezes.
Friday is set to be cold with bright or sunny spells and scattered wintry showers, heaviest and most frequent in the west and north and well scattered further east. Highest temperatures of 3 to 6 degrees with light breezes.
Friday night will be very cold with frost and icy patches developing.
Saturday and Sunday are expected to continue very cold with sunny spells and scattered wintry showers. Highest temperatures ranging from 2 to 6 degrees. There will be widespread frost both nights with temperatures dropping to -4 degrees in places.
Current indications for next week suggest Monday will continue very cold with further wintry showers and frost at night.
