On Saturday morning a rouge warm front ahead of the real warm front for Sunday will attempt to make inroads in to the colder air. It will fall short over the country and slide southeast but in doing so it will bring snowfall for a time over the northern half of the country and there will be some accumulations before it clears eastward.
1 - 3 cm on lower ground, more with height.
Not a fan but just to illustrate.
On Sunday a more active system is likely to bring snowfall to west Ulster, rain for the rest of us.
Higher ground always the wrong place to be this weekend.
Alas, it is this system that heralds the end of this colder spell of weather and a temporary rise in temperatures along with southwesterly winds that could be strong at times thereafter for a good part of next week.
Mod Note : adding warning
National Weather Warnings
Snow-ice Warning for Cavan, Monaghan and Donegal
A band of heavy rain will move up from the south on Saturday night. The rain will turn to sleet and snow in places as it encounters the cold air with temporary accumulations possible. Snowfall accumulations will be highest in upland parts of Donegal. Any snow will turn back to rain later on Sunday morning as much milder air extends from the south.
Issued:Saturday 20 January 2018 11:00
Valid:Saturday 20 January 2018 23:00 to Sunday 21 January 2018 08:00