Seasonal trend: Towards colder than expected winter?

We have mentioned it regularly in our articles or Seasonal trends In recent weeks, the probability of winter 2020-2021 is generally seasonal, so it is colder than previous winters. This trend can be well stabilized and even go in that directionA winter is a little colder than normal According to the latest analysis of our forecasters. Let’s remember that Last winter turned out to be milder than average, Which continued for 7 years. The situation may change for the better this year, let’s see why …

Against the waves of some weather patterns that continue to sign up in very mild winters until February, We think the latter will hold us by surprise After a more mild December. Except, Since Christmas we have a protracted winter, Not to mention a cold event. Long-term vision forecasts warming in the second decade of January, but The latter may be temporary Somehow we were able to find out More winter conditions again in the last decade or even in February.

Two clues lead us to think that the rest of the winter may be cold. First Girl, The equator is a phenomenon that affects the temperature of the ocean surface in the central and eastern parts of the Pacific, and thus there is a shortage of surface water. This type of phenomenon has implications for global climate, By lowering global temperatures, a link between La Nina and the European climate can actually be left unproven, but beyond doubt.

Evolution of temperature at 10hPa (30 km) altitude. Sudden layer warming is visible in early January 2021 (red curve). Credit: CPC-NOAA

Another event, for its importance, if not more significant, The temperature of the stratosphere. The latter has a direct influence on important weather, including the old continent. Earlier this month, we saw what was called Sudden stratospheric warming. The latter has rapid and strong effects on the polar vortex, which then propagates. In other words, A polar vortex called “decentralized” supports a ripple regime at the level of the Northern Hemisphere, Which is positive Cool air downwards More or less malignant.

It remains to be seen where these descendants of the cold wind will intervene in the coming weeks. It is very difficult to understand these types of ripples and their path for more than ten days. That’s for sure The likelihood of a winter jump in early January is much higher than in previous winters…

In the coming weeks we saw many weather clues here that are conducive to cold spells in Europe or elsewhere in the Northern Hemisphere, not to mention that a cool photo is coming, especially in Western Europe. However, this article can be considered a foretaste. We call for our advice Trends in 3 weeks Or ours Seasonal trends Learn more.