Met Eireann are forecasting a freezing night with temperatures dropping as low as -3C in parts of the country.
The bitterly cold weather is not normal for May but shouldn't stick around for too long, with a milder weekend forecast.
Here's what's in store over the coming days.
Thursday night
Tonight will be largely dry and clear, with just light isolated showers near northern or northwestern coasts.
Frost will form though as the temperatures drop between -3 and +2 degrees, coldest in the midlands.
Friday morning and afternoon
A cool and dry and bright start to the day is expected with some scattered showers in Ulster and northern parts of Connacht.
Elsewhere, the odd shower will arrive as clouds build through the afternoon. A spell of rain will arrive in the southwest during the evening though.
Friday night
It's an evening for staying indoors because it's set to be wet and windy. The rain will spread from the southwest overnight, reaching the northeast at around dawn.
Sadly, the rain will be heavy at times, particularly along the southern coast, where winds will reach gale force on coasts in the southwest and west.
Saturday morning and afternoon
The wet and dreary conditions will carry into the morning but the rain is expected to clear the north coast in the afternoon, leaving sunshine and showers. A milder day than the previous ones is expected, with the highest temperatures ranging between 13 to 17 degrees, mildest in Leinster.
Saturday night
Sadly, the conditions will turn with showers becoming more frequent and widespread.
Sunday morning and afternoon
Sunday will be windy with heavy showers across the country.
It's shaping up to be rather bleak with Met Eireann saying there will be "limited bright intervals. Hail showers are possible, with the risk of thunderstorms. Showers will likely be heaviest in the western half of the country."
Sunday night
Showers will continue on Sunday night mixed with clear spells.
Monday
Next week will see even more widespread heavy showers of rain or hail, with thundery downpours possible too. Yet again, any bright or sunny spells will be limited.
The remainder of next week
It will continue to be unsettled with low pressure dominating. This will likely bring showers to most areas with temperatures staying at an average or slightly below average level.
