The crazy summer continues. In the last week of August, the extreme expansion of the Azores high is responsible for this.
Munich – The weather has relatively little to offer sun lovers in summer 2021. So far it has only been really warm on a few days – and short but extreme heat waves resulted in destructive storms and heavy rain. Anyone who wished for a few more days in the outdoor pool at least in the last days of August will now find it bitter, because the bad balance continues. In the last week of August, the temperature is around five degrees below the climatological average for this period. And not only that: August ends this year with a curiosity. At 23 degrees, higher temperatures are expected on Iceland than in Ingolstadt in Bavaria, 1500 kilometers further south. That reports weather.com. But how does it come about?
The surprising temperature conditions are caused by an Azores high that extends over Iceland and all the way to Greenland. It is also the cold air from Greenland that most parts of Germany will get. In the course of this expansion, warm, subtropical air from the Azores high also flows into Iceland. At least the north of Germany will get a little of this warm pinch in the coming week.
Azores high leads to strange weather: German Ingolstadt is colder than Iceland
For the rest of Germany, however, the next few days will see temperatures drop to around 20 degrees. Only on the Rhine can values of up to 25 degrees be expected in isolated cases. The coldest day of the week is expected to be Tuesday – in southern Germany the temperatures will then drop to 15 degrees. On Wednesday there was the miraculous development that just 19 degrees are expected in Ingolstadt in Bavaria, while temperatures in Iceland reach a comfortable 23 degrees.
But not only Germany and Iceland are affected by this extreme situation. The vast extent of the Azores high has a global impact. At the edge of the high, polar cold air penetrates as far as Hawaii, for example – while a heat wave threatens in the north-west of the USA.
What is the Azores high?
At the equator, air warmed by the sun rises upwards and flows several kilometers above the ground towards the poles. These air masses sink again approximately between 25 and 40 degrees north and south latitude, creating several high pressure areas. They form the subtropical high pressure belt. The Azores high belongs to the subtropical high pressure belt of the North Atlantic.
The Azores high arises near the eponymous archipelago over the Atlantic Ocean on a vortex of one of the large jet streams that move around the earth at a greater height. Therefore it is very stable and also stationary for a long time. However, the high pressure belt moves with the seasons – and so does the Azores high.
In general, the Azores high and the Iceland low play the decisive role for the general weather conditions in Europe: Usually the low pressure systems (cyclones) driven by the general west drift in the northern hemisphere come at mid-latitudes from the North American coast across the Atlantic (Atlantic west weather). Depending on the characteristics of the two systems, the low pressure eddies are shifted to the south or north, so that the individual areas of Europe are hit by the center, by the warm front or the cold front.
Weather in Germany: Outlook for the coming week
Rain is to be expected on Monday, especially in the east and south-east. “Thunderstorms from the Emsland and from eastern North Rhine-Westphalia via Lower Saxony to Lusatia and the Berlin area, and storms from the Harz due to heavy rain, sometimes lasting several hours, cannot be ruled out,” reports the German Weather Service (DWD). Thunderstorms and thunderstorms can also be expected in the south-east during the course of the day.
In the west and southwest it is sunny, slightly cloudy during the day on Monday. The maximum values in the rainy east and south-east are around 18, otherwise 20 to 24 degrees. On Tuesday the temperatures drop to 18 to 24 degrees. Wednesday will be increasingly cloudy in the north and rain will come during the day. The maximum values are 19 to 24 degrees.
Shortly before the weekend, inconsistent weather, repeated showers and heavy rain can be expected again. A local exceeding of warning thresholds is also not excluded. According to the current forecasts, but so far rather unlikely, reports the DWD.