Temperatures are expected to top those in the Algarve over Easter weekend - with some of the highest temperatures NI has experienced so far this year.
Richard Miles from the Met Office said: "It is warming up all week towards Saturday - which will be the warmest day over the weekend.
"Saturday should be in the low 20s.
"It will be a nice day everywhere and it could be 21 or 22 degrees in parts of Northern Ireland.
"Easter Sunday will be a little bit cooler as there is a little uncertainty with weather fronts coming from the west.
"It is still likely to be fairly pleasant but not as warm and clear as Saturday is expected to be.
"It will be slightly cooler so maybe something in the high teens. But you might, in sheltered areas in the sun, see higher temperatures of maybe 22/23 degrees."
Mr Miles added there is "uncertainty" around forecasts after Easter Sunday.
"It is expected to be more unsettled in more westerly areas of the UK, with more cloud and rain over Northern Ireland and Wales," he added.
"But still temperatures are much higher than normal - as normal temperatures for this time of year are around 12 degrees.
"Temperatures in the mid teens are plausible for Easter week.
"You will see dry spells and sunshine," he said. "It is looking fine, sunny and warm for most places."