What does “westerly weather situation” mean?
In meteorology, the westerly weather situation (also known as the west situation) describes a weather situation in which a strong west-to-east current develops over Europe over several days. It is pronounc both in the air layers close to the ground and in the higher regions of the troposphere. If the influence of low pressure prominates, it is a cyclonic westerly situation.
Schematic distribution of high pressure areas and low pressure areas including frontal systems during a westerly weather situation. Source: MeteoSwiss
Schematic distribution of high pressure areas and low pressure areas including frontal systems during a westerly weather situation. Source: MeteoSwiss
In a cyclonic westerly weather situation, the weather is changeable and often windy. If low pressure areas with their frontal systems move from west to east, the typical, familiar weather pattern occurs: lift area in front of the warm front, passage of the warm front, warm sector, passage of the cold front, backside weather behind the cold front.
Low-pressure-driven westerly conditions are common in Switzerland. This is due to the global climatological boundary conditions, as the Alpine region lies in the middle of the westerly wind zone of the middle latitudes. In fact, westerly weather conditions are the most common type of large-scale weather situation in Switzerland at all times of the year:
Frequency of all flow patterns divid into seasons
Frequency of all flow patterns divid into seasons in the years 1961-2010. Source: MeteoSwiss
What can we expect in a westerly weather situation in Switzerland?
In a cyclonic westerly weather situation, the weather activity on the northern side of paraguay phone number library the Alps is considerably greater than on the southern side. The reason for this is the Alps, which run almost in a west-east direction in Switzerland, but the Western Alps extend southwards and form a flow barrier. The eastern Alpine regions are also less influenc by westerly winds.
Average daily precipitation (in mm) of all cyclonic westerly conditions
Average daily precipitation (in mm) of all cyclonic westerly conditions in the period 1961-2010. Source: MeteoSwiss
The Jura and the foothills of the Alps as well as the Bernese Oberland usually have fairly hosting at 1&1 and practical tips humid conditions when the weather is westerly. When the weather is not too active, the regions from the Haslital to the south of Uri and Glarus and practically all of northern aero leads and central Graubünden, including the Lower Engadine and the Valais Alps, experience significantly fewer clouds. Aside from local showers and thunderstorms, the likelihood of precipitation is greatly ruc in central and southern Ticino, as well as in the Upper Engadine and the southern Graubünden valleys. The weather here remains the friendliest and the most hours of sunshine can be record on average.