which are classified as hot semi-arid (BSh) because of the low annual rainfall, have not recorded temperatures as high as other places in the city. This occurs due to the moderating influence of the sea, and lower levels of industrialisation compared to other regions of the city. Owing to the rain shadow of the Pindus Mountains, annual precipitation of Athens is lower than most other parts of Greece, especially western Greece. As an example, Ioannina receives around per year, and Agrinio around per year. Daily average highs for July have been measured around in downtown Athens, but some parts of the city may be even hotter for the higher density of buildings, and the lower density of vegetation, such as the center, in particular, western areas due to a combination of industrialization and a number of natural factors, knowledge of which has existed since the mid-19th century. Due to the large area covered by Athens Metropolitan Area, there are notable climatic differences between parts of the urban conglomeration. The northern suburbs tend to be wetter and cooler in winter, whereas the southern suburbs are some of the driest locations in Greece and record very high minimum temperatures in summer. Heavy snow fell in the Greater Athens area and Athens itself between 14–17 February 2021, when snow blanketed the entire city and its suburbs from the north to the furthest south, coastal suburbs, with depth ranges up to in Central Athens., and with even the Acropolis of Athens completely covered with snow. The National Meteorological Service (EMY) described it was one of the most intense snow storms over the past 40 years. Heavy snow was also reported in Athens on January 24, 2022, with reported locally in the higher elevations. Athens is affected by the urban heat island effect in some areas which is caused by human activity, altering its temperatures compared to the surrounding rural areas, and leaving detrimental effects on energy usage, expenditure for cooling, and health. The urban heat island of the city has also been found to be partially responsible for alterations of the climatological temperature time-series of specific Athens meteorological stations, because of its effect on the temperatures and the temperature trends recorded by some meteorological stations. On the other hand, specific meteorological stations, such as the National Garden station and Thiseio meteorological station, are less affected or do not experience the urban heat island. Athens