by EFAS Meteorological Data Collection Centre

August 2020 was characterised by roughly normal monthly mean surface pressure in the EFAS domain, only lower than normal around Spitsbergen. Monthly precipitation totals were below the long-term means in an arc from northern Africa over the Black Sea towards Scandinavia, with an extension to the Iberian Peninsula and above normal elsewhere. Monthly mean air temperatures were below the long-term means from western Russia to Iran and Turkey as well as at the western Iberian Peninsula while positive anomalies occurred in the other parts of the EFAS domain.

At the beginning of August 2020, the Azores High was around its usual position and a low-pressure system was located near Iceland, and another one over northern Russia, which brought notable precipitation amounts in this region in the first days of August. Even as the low-pressure system near Iceland weakened at the surface, an upper-level trough extended with a cold air advance towards central Europe. This caused intense rainfall at the Alps and in the higher parts of the mountains enough snowfall for skiing. Some local floods appeared in the region.  An upper-level low-pressure system was cut-off from the trough and moved along the Adriatic Sea, bringing intense rain to the western Balkans and Italy. In the same days, yet another low-pressure system moved from the Atlantic Ocean to Iceland and brought significant precipitation amounts to Great Britain and Ireland. The high-pressure system from Russia extended south-westwards, developing a new core over the Baltics, which moved to Scandinavia and later back to the Baltics. A trough developed over the eastern Atlantic Ocean towards the Iberian Peninsula and caused severe weather in Spain, the United Kingdom, and France. Another upper-level low-pressure system developed westward of Great Britain and Ireland, moved across the Gulf of Biscay and English Channel to Great Britain and Ireland, where it merged with a very strong low-pressure system coming in from the Atlantic Ocean. It brought strong winds to Great Britain and Ireland and later to western Scandinavia as it moved there. Only a few days later, another low-pressure system developed and intensified very fast over the eastern Atlantic Ocean and moved across Great Britain and Ireland, and the North Sea towards the Baltic Sea bringing very strong winds along its track. Worth mentioning is also a low-pressure system over the Kola Peninsula. Both low-pressure systems brought notable precipitation amounts. A few days later, another low-pressure system moved on a similar track from the Atlantic Ocean to the Baltic Sea. An upper-level trough developed from this low-pressure system over France and detached from it, moving slowly eastwards and causing again heavy precipitation in and around the Alps. This was a similar situation as at the beginning of August, but it brought rain also at its eastern edge and to southern France and the Balearic Islands.

In August 2020, the highest precipitation totals were observed over the Alps, Balkans and Great Britain and Ireland (Figure 1). No or almost no precipitation fell in the south of the EFAS domain, in the south of the Iberian Peninsula, and some regions to the north of the Black Sea. Monthly precipitation totals below the long-term means occurred in the Scandinavia, north and south of the Black Sea, the Baltics, in parts of south-western and central Europe, and in the south of the EFAS domain (Figure 2). Monthly totals above the long-term means were reported in the centre of the EFAS domain but also around the Caspian Sea, Great Britain and Ireland, and parts of the Iberian Peninsula. 

The monthly mean air temperature ranged from -2.5°C to 38.2°C with the highest values in the southern parts of the EFAS domain. The lowest temperature values were reported in the northern and mountainous regions (Figure 3). Air temperature anomalies ranged from -5.8°C to 7.9°C (Figure 4). Monthly mean air temperatures below the long-term means occurred from western Russia southward to Iran and Turkey, in parts of Scandinavia, and the Iberian Peninsula. Positive monthly mean temperature anomalies were reported in other parts of the EFAS domain.