Met Éireann are forecasting temperatures to go as low as 1 degrees Celsius tonight in Kilkenny and the cold snap is expected to last throughout the weekend.
The forecaster said: "Cloudy skies for many places tonight with frost limited to parts of Munster and south Leinster where cloud cover will be more patchy. Lows of 0 to 4 degrees, coldest in the south."
According to www.kilkennyweather.com, the minimum air temperature today was -1.6 degrees Celsius at 07:54am.
The lowest air temperature last month was -2.9 degrees Celsius and it occurred on November 17.