Both Finner and Markree weather stations recorded higher than normal temperatures in the month of May.
According to Met Éireann, the average temperature at Finner was 1.9 degrees Celsius above the long-term average at 12.8 Celsius.
Markree meanwhile was 1.6 degrees Celsius higher than average at 12.5 Celsius.
Both were part of, according to Met Éireann, the warmest May on record.
Temperatures nationally were on average 13.08 degrees Celsius, more than 2.5 degrees above the long-term average.
Met Éireann have also confirmed last month was only the second time in 125 years that the average temperature for May exceeded 13 degrees Celsius.