Met Eireann are warning of sub-zero conditions within just days as a spell of cold weather is set to hit Ireland.
The first signs of winter are expected towards the end of this week, with values reaching -1C in places overnight on Sunday.
Expert Alan O'Reilly from Carlow Weather explained that Sunday will be the day that brings the first noticeable changes, which will continue through next week.
He wrote: "Very little rain showing on weather models but temperatures heading down from Sunday and a few cold snaps possible next week. The heating bills are going to start ramping up!"
He added: "Latest charts from GFS weather model for upper air temperatures. You can see milder weather for next couple of days gives way to much cooler air from Sunday and then possibly second blast of cold later next week.
"Latest ECMWF forecast also shows plunges of cold air but could be short lived."
Meanwhile we can still enjoy the last of the relatively mild weather on Friday, with highs of 13C and largely dry conditions.
A Met Eireann forecaster said: "A largely dry day on Friday and mostly cloudy again, with occasional bright spells. A few patches of rain or drizzle will occur, mainly affecting southern and western coastal areas and hills. Highest temperatures of 10 to 13 degrees in moderate southwest winds.
"Generally cloudy overnight with a few patches of drizzle or mist. Persistent rain will develop in the northwest towards dawn on Saturday. Minimum temperatures of 7 to 10 degrees in moderate southwest winds.
"On Saturday, a band of rain will spread across Connacht and Ulster during the morning, extending southeastwards to remaining areas of the country in the afternoon. A clearance to colder conditions with scattered showers will follow across the west and north later in the day. Moderate southwest winds will veer northwest during the day and increase fresh. Highest temperatures of 9 to 12 degrees but turning colder later in the day.
"Cold and breezy on Saturday night with showers affecting western and northern coastal counties, some with hail. Elsewhere, it will be mainly dry with long clear spells. Minimum temperatures of 2 to 5 degrees in moderate to fresh northwest winds."
And conditions are set to turn very cold from Sunday onwards, with overnight lows reaching -1C on both Sunday and Monday.
A forecaster added: "Sunday looks set to be a cold and blustery day with sunny spells and some showers. The showers mainly affecting coastal districts of the west and north, perhaps a few drifting in along Irish Sea coasts. Some of the showers will be of hail. Maximum temperatures of 6 to 9 degrees in brisk northerly winds. Cold and mainly dry on Sunday night with long clear spells. Frost is expected to form widely across the country with lowest temperatures of -1 to +3 degrees in light northerly winds.
"A cold and crisp start on Monday with frost clearing during the morning to leave a dry and bright day with spells of sunshine. Maximum temperatures will range from around 6 to 9 degrees in light variable winds. A cold night on Monday night with frost and some fog patches. However, frost will clear from northern counties later as cloud thickens bringing a few patches of light rain or drizzle there. Minimum temperatures of -1 to +4 degrees.
"Frost is expected to clear from southern counties on Tuesday morning with cloud and a few spots of rain spreading from the north. It will stay mostly dry during daylight hours albeit with plenty of cloud and a few patches of drizzle. Highest temperatures of 7 to 11 degrees in a moderate west to northwest breeze."
