Record low temperatures were set in Greece during the period 1/5-3/5 of 2026 due to a cold invasion accompanied by widespread snowfall in many areas of the country.

This is according to the ClimateHub information hub of the National Observatory of Athens. According to ClimateHub, which is the first national initiative to implement the Copernicus Climate Change Service (C3S) in Greece, these temperatures are considered unusually low for this time of year, and, according to measurements from the historic EAA climate station permanently installed on Nymph Hill (Thiseio) since 1890, broke a previous record on a centennial scale.

With an average 24-hour temperature of 13.3°C, the First Monday of 2026 was one of the coldest ever recorded in Athens. More specifically, as ClimateHub points out, it was the 4th coldest in the last 135 years, with the coldest May Day being that of 1944 (12.1°C), followed by May Day 1987 and 1988, with average temperatures of 12.73°C and 13.2°C respectively. According to the historical climate records in Thiseio, the hottest May Day was that of 2013, where the temperature during the day reached 31.8 °C, while the May Day of 2012 was at similar levels, with 31.4 °C.

In addition, as ClimateHub notes, strikingly low temperatures also prevailed on the following days, namely May 2 and 3, 2026, where 24-hour average temperatures ranked as the 2nd coldest day for those dates since 1890.

At the same time, according to ClimateHub, the 24-hour maximum temperature on 2/5/2026 in Thiseio was 15.2°C, the lowest maximum temperature ever recorded (since 1890) for that day, breaking all previous records.

“Although the climate is also characterized by strong natural variability, it is very likely that this phenomenon is linked to the effects of climate change. It is established that global warming (and indeed asymmetric global warming) affects the atmospheric circulation and consequently the intensity, geographical distribution and seasonality of various weather systems such as cold or warm invasions.” ClimateHub underlines and adds that “regardless of the unusually low temperatures observed in early May, the general trend of the May temperature in Athens is increasing, with an average temperature increase rate equal to 0.44°C/decade since the 1980s. The rate of increase is even higher at minimum (night) temperatures and exceeds 0.6°C/decade.”

Note that the maintenance of the EAA’s Historical Climate Station, as well as the collection, management and quality assurance of the data, is carried out by the EAA’s Institute for Environmental Research and Sustainable Development.