This morning has seen the first real chill in the air as a cold polar airmass and longer nights set it.
According to this morning’s 0600 UTC synop reports the coldest station last night was Gurteen in Co. Tipperary, where clear skies allowed the air temperature to fall to 1.1 C and the grass temperature to a frosty -2 C. Second coldest was Casement, Co. Dublin, on 2.4 C air and -1 C grass, with nearby Dublin Airport on 3.5 C air and +1 C grass. Finner, Co. Donegal, also reported a grass min of -2 C, though the air temperature only fell to +3.7 C.
Mt. Dillon in Co. Roscommon was reporting 2 C air temperature on met.ie at 7 am but as no synops are issued for that station or the other recently-added automatic stations we will have to wait until tomorrow for the exact figures for all stations.
It wasn’t widespread cold, however, as the south was enjoying temperatures above a “balmy” 9 C (Sherkin Island 9.6 C). Along the coast the sea, which is at its warmest now, keeps the temperature much higher than inland, where clear skies allow the land to lose longwave radiation to space, causing the low ground-temperatures and hence chilly air-temperatures.