Rain and sleet, as well as some snow on higher ground, will sweep across the country on Wednesday and into the early hours of Thursday as a low pressure system moves in from the west.
The low pressure system will form over Baffin Island before tracking east southeast towards Ireland moving over cool and moist polar maritime air as it does so, with the jet stream to its south acting as a conveyer belt to its final destination in Ireland and Britain (see below).
Precipitation totals are not expected to be significant widely but localised downpours could occur almost anywhere. The middle band of the island stretching from Clare to Dublin is likely to see the highest precipitation totals, ranging from 10mm to 15mm. Northern counties will see the lowest totals.
Any snow will be restricted to the highest peaks until Wednesday evening and night when cooler temperatures wrapped around the back end of the system will result in rain turning to sleet and snow for a while in places. Widespread snowfall is unlikely with any wintry precipitation likely to only affect higher ground in inland regions of Ulster and Leinster.
Daytime temperatures on Wednesday will range 5-8c but will drop towards evening. Night-time temperatures will range -1c to 2c.
Winds will initially be moderate west-northwest with gentle southerly winds initially in the north and east of Ireland. Due to the rotating low pressure system crossing the island, the winds will later back southerly before turning strong to gale force north-northwest. Winds will remain gentle westerly for southern coastal counties for the entire day. The winds will turn moderate northerly everywhere during Thursday.
On a positive note, Thursday and Friday look like being largely dry days with just well scattered showers of rain, hail or sleet. Rain and sleet will clear eastern counties on Thursday with drier and brighter conditions following for all parts with scattered showers affecting the northern and eastern coast. Friday will be dry and sunny for most parts of the country with daytime maximum temperatures of 5-7c in gentle northerly winds.