Arctic air will move down across northwest Europe late on Monday into Tuesday.
With high pressure situated to the north of Ireland, a cold continental airmass will be pulled in across Ireland and Britain by mid-week.
Daytime temperatures will be 6-9c at best from Tuesday with overnight frosts developing.
Showers will affect eastern coastal counties, but there will be a good deal of dry and bright conditions overall.
Some falls of sleet or snow are likely on the mountains where precitipation does occur.
Winds will be moderate northeasterly at the beginning of the week, but will turn lighter and more variable in direction as the week progresses.