A low pressure system is intensifying in the Atlantic and under certain conditions can cause a significant change in the weather in November.
TIn the coming days, low pressure will expand southward in the Atlantic, pushing warm and moist air masses northward on its eastern flank Germany, Austria and Switzerland came under high pressure in the middle of the week.
It will remain unusually warm for the time of year
The combination of a southwesterly flow and a high over Germany causes the temperatures to rise – widespread – to +15 to +20 degrees and over the south up to +24 degrees locally may be possible. There is always up to and including Tuesday local showers, which can provide some variation. From the middle of the week the weather will gradually dry up fog spreading can be expected with increasing sunshine duration. Speaking of fog – if this dissolves only hesitantly, they fail temperatures at the +15 degree mark. More on this in the current weather forecast for October.
The rain forecast
Significant precipitation will move southeast today and it will remain largely dry Sunday night. A few showers will cross Germany on Monday and Tuesday, which could be significant and productive south of a line from the Black Forest and Dresden. Another area of precipitation will reach Germany on Tuesday evening and move south of a line from Cologne and Dresden across Germany on Wednesday evening.
If you accumulate the precipitation up to and including Thursday, then is north of the line from Cologne and Dresden total rain expected from 0 to 5 l/m² and on the coasts up to 8 l/m². It remains widespread dry. The situation is different to the south, where the rainfall yield can be between 5 and 15 l/m² and locally up to 25 l/m². Up to 30 l/m² may be possible along the Alps and in the traffic jams of the Black Forest.
What will the weather be like in November?
The south-westerly weather situation has emerged as the favorite in the last few days, affecting the weather over Germany until the end of October and in certain conditions October could bring a new record. The emphasis is on could, because if you add them together weather forecasts of the prediction models, the deviation from the average of 1961 and 1990 is in the range of +3.1 and +3.6 degrees. Of record goes back to 2001 with a deviation of +3.5 degrees.
Will November also start significantly too hot?
We would like to pursue this question today. To do this, let’s take a look at the marginal factors.
The NAO index is currently neutral with the trough extending far to the south. What is the NAO index? To put it very simply, the NAO index reflects the relationship between the Icelandic low and the Azores high. If it is positive, a control level is established over Iceland (weather conditions from west to south-west). If the NAO index is negative, a high pressure system has been able to position itself over Iceland (northwest to north weather conditions). Neutral has no clear reference, much is theoretically possible. Since the current calculations involve a trough in the Atlantic, it is South-westerly weather conditions are setting in over Central Europe at the moment.
The pressure anomalies
The neutral NAO index becomes more evident in the pressure anomalies. The low pressure center is mostly stuck in the area between Iceland and England until early November, while the Azores high deviates to the west and wedges over the Mediterranean. Only when the low point is resolved and drifts on to Scandinavia is it over Autumn perspective interesting.
If you compare the pressure anomalies on 1 November with the mean value of all control runs, you can see the parallels. It is worded in a different way weather that is considerably too warm for the season until early November.
What if the low shifts to Scandinavia?
It shows that such a thing is possible Forecast of the Americans though should be treated with caution due to the extremes.
Why extremes? The Atlantic low pressure center continues to strengthen until November 2 and is pushing hard towards Scandinavia, but faces two obstacles to overcome. On the one hand the trough over the Atlantic – which continues to pull the Atlantic frontal zone southwards towards the Azores – and on the other hand there is the blocking high over Europe. But it doesn’t matter – the low point continues to intensify and it actually manages to expand to Scandinavia.
autumn storm? Possible!
In this case, expansion does not mean displacement – this is an important difference, where Germany, Austria and Switzerland are only grazed by the force of the frontal zone. Whether northern Germany can be from November 1 brings the first autumn storms into playwhile not much happens further south.
Too much dynamics is also not good
But if you want to achieve something with all the power, it often turns into the opposite of what you really wanted to achieve, and that’s how the Atlantic frontal zone feels. They are already learning November 3 an error in the form of a high-pressure system that wedges itself northward on the Atlantic towards Iceland and Greenland. The high begins to block the supply of low pressure systems and chokes a zoning phase (westerly weather conditions) at the beginning.
Full autumn – right?
As the Atlantic high is wedged to the north, there should be room to maneuver over Europe of a meridional north-south current. Yes, it is possible, but Americans see it in their present Forecast something else, because there is still a trough ahead of Central Europe. And it is precisely this trough that pulls the entire low-pressure structure south of Central Europe, and in extreme cases Germany, Austria and Switzerland remain in one’s sphere of influence. unstable and warm southerly flow of the air masses.
How hot can it get? In their temperature forecast, the Americans calculate values of +12 to +16 degrees for November 2 and +14 to +18 degrees for November 6. Full autumn certainly looks different.
In a Nutshell: Weather Change? Slow!
The unusual and warm general weather situation will not be able to last forever in the Atlantic, but it is already showing one significant conservation tendency.
First warmer, then milder
Also noteworthy because the control runs are scheduled for October 28 calculate an average overtemperature of up to + 10 degrees – remember the mean value! Subsequently, the level gradually decreases, showing an excess of +1 to +4 degrees on November 1, and on November 7, the level continues to normalize with a difference of +1 to +2 degrees. It will be too hot for the season, but the overall weather situation changes in November.
But if this results in a general weather situation that Storm, wind and rain are a clear step closer to autumn, may be in doubt for the moment. Why this is so can be seen in the precipitation forecast for the control runs. Significant precipitation signals are not really discernible from October 26 to November 7. While northern Germany may benefit from a maritime influence, no more than a few occasional showers are expected southbound.
fog and high fog
But how does high pressure weather relate to falling temperatures? Quite simply – the nights are clear and cool down more. And you can too Fog forms at night, which dissolves only hesitantly during the day and thus dampens the temperature level.
The high pressure dominance can be seen more clearly in the mean value of all control runs.
|Day||temperature spectrum||average temperature|
|October 28||+16 more
|November 1st||+10 more
|November 6||+5 more
The long-term model weather trend
That this The weather in November 2022 can not only start too hot, but the further course can also be too hot, shows in the current one Forecast for the long-term model. The temperature deviation from the long-term average is +1 to +2 degrees, and the trend is up to +2.5 degrees essential for hot area (91/20: +0.2 to +1.7 degrees). The precipitation forecast remains unremarkable and the trend to the south is a little too dry.