Ireland's current unusually hot weather is as a result of tropical maritime airmass sitting over the country.
Temperatures are nearing 20C in parts of the country today with sunny spells and a late blast of summer for most.
But, a change is coming with more seasonable chilly temperatures to be felt before the week is out.
A Met Eireann forecaster said today: "A very mild start to this week as a tropical maritime airmass lies over the country, but with low pressure dominating it will be rather wet & unsettled at times.
"A change on the way later this week though as a polar maritime airmass brings cooler, more settled weather."
Wednesday night looks to be the point where the colder conditions will take over with the mercury dipping to 4C, some 16C colder than Monday's heat.
The forecaster said: "Becoming quite blustery on Wednesday evening and night with westerly winds veering northwesterly and increasing strong to gale force on coasts. Starting dry in many areas but outbreaks of rain will push down over the country from the west and north overnight. Minimum temperatures will down to between 4 to 7 degrees Celsius."
And that cool and windy weather will continue right into the weekend with a mixed bank holiday in store.
The forecaster added: "Largely unsettled over the weekend with wet and breezy weather at times as showers and spells of rain spread from the Atlantic."
