The crossroads in January, between the European cold and the unknown of the February weather
Table of Contents
(METEOGIORNALE.IT) There’s no point in going around it, this winter seems to constantly be playing hide and seek, often leaving us caught between the nostalgia of the seasons of yesteryear and yesteryear. climate reality which appears increasingly distorted. We are now halfway there Januaryyet the dominant sensation is that of one great uncertaintyalmost as if the atmosphere had not yet decided which mask to wear for the season finale.
By observing the latest projections of the mathematical models, integrating both the readings of the European weather centre than the American ones of GFSan extremely dynamic picture emerges, I would dare say fluid, where the cold tries to make its way towards theEuropa central, despite having to deal with one Atlantic resistance never completely tamed. It is no mystery that the long-term forecasts are volatile, indeed, in this period the their reliability drops drastically once the five days of validity have passed. In short, what seems like a certain event today could turn into yet another tomorrow heat bubble out of seasonmaking the work of analysis an exercise in continuous prudence.
Europe in the crosshairs of Arctic currents
Taking a look at the situation on a continental scale, it can be seen as one vast mass of cold air is trying to regroup between the Russia and the Scandinavia. It is the signal that the Polar Vortex It’s not as compact as some might think. This icy reservoir, which in the heat maps at 850 hPa presents itself as one purple tongue ready to descend in latitudepoints decisively towards i BALKANSalso partly touching theItalia. Data from the American model GFS highlight, right around the January 22ndand nucleus of freezing air with temperatures down to -20°C or -24°C at an altitude of approximately 1500 meters positioned between the Russia European and the Finland. But be careful, because talking about historical cold waves would be a gross mistakeas well as scientifically incorrect. What we are observing is rather an attempt to return to climate normality, a process which however occurs amidst a thousand difficulties and sudden setbacks.
The arctic air flow, descending in latitude, encounters the obstacle of mountain ranges and the resistance of high pressures. In fact, the baric maps show an impressive high pressure field, with values close to 1041 hPa, which stabilizes on theEuropa northern around the end of the second decade of January. This invisible “wall”. has the task of diverting or blocking the Atlantic currents, favoring, on the other hand, the sliding of colder air towards the southern edges of the anticyclone. Yet, the trend for the third decade of January seems to indicate one greater vulnerability of the Mediterranean. There is a real risk that a series of disturbances manages to infiltrateattracting increasingly colder air. In Germania, Poland and even in Francetemperatures could drop significantly below zero, bringing widespread snowfall. But what role will Italy have in all this? We are, as often happens, the borderland, the place where different air masses collide, generating thermal contrasts that are sometimes spectacular, sometimes dangerous.
The meteorological puzzle over Italy
As for our country, the weather evolution it still is all to be written and current projections show divergences that call for caution. The maps indicate that the Northern Italy it could be the area most exposed to possible snowfall, especially if cold currents manage to enter through the Bora gate. It cannot be ruled out that, between January 22nd and the January 27episodes of snow may occur up to the plains or even along the coasts of the upper Adriatic. However, these are hypotheses that need confirmation in the next few days, since a minimal movement of the low pressure center is enough, currently expected to form between the Ionian and the Adriatic already towards the January 17thto transform a potential snowfall into an insistent rain.
Let’s say it clearly, the illusion that we are returning to the winters of the pastthose with ditches frozen for weeks, is just an illusion. Current thermal averages are heavily influenced by positive anomalies that make each cold episode an isolated eventalmost an exception that confirms the rule of Global Warming. Even if we were to experience a week of intense cold, the data tells us that global temperatures remain at worrying levels. In fact, the trend of the winter quarter is often altered by sudden rises of the African anticyclone, which in a few hours can cause the mercury column towards spring valuesi, especially in the South and on Islandslike the Sardinia and the Sicily. This alternation between winter flurries and mild out-of-season flare-ups is the new signature of the Mediterranean climate.
What is Arctic amplification and why does it concern us
To understand what’s happening above our heads, we need to look much further north. Many scientific studies, many of them published in United Statesthey are focusing on a phenomenon called Arctic Amplification. But what is it exactly? To explain it simply, it is the phenomenon whereby the North Pole it warms much faster than the rest of the planet. This reduction in the thermal gradient, i.e. the temperature difference between the polar and tropical regions, has a direct effect on the jet streamthat ribbon of high-altitude winds that drives disturbances.
As this thermal difference decreases, the jet stream becomes weaker and begins to form large undulationsa bit like a river that slows down its flow and creates meanders. These “waves” allow warm air to rise towards the pole and, at the same time, freezing air to descend towards lower latitudes. This explains why we can go from an almost summer Monday to a Thursday of round snow. These extreme weather events, both heat and cold, are precisely the result of a system that seeks an increasingly difficult balance to find. THE’Arctic Amplification it is therefore the engine that stirs the winter atmosphere, making forecasts a real headache for meteorologists around the world. It is a sort of thermal slap that the atmosphere gives us back to compensate for global energy imbalances.
Strong winds and storms, the dynamic face of January
It’s not just the thermometer to keep an eye on. The wind and geopotential maps show how the passage of depression systems can unleash storm gusts on many sectors. The Tyrrhenian Sea and the Ligure Sea they could be lashed by mistral and south-westerly winds, with gusts that could exceed 100 kilometers per hour in open sea. This dynamism is typical of a season that tries to shake off the anticyclonic staticity, but brings with it risks that should not be underestimated for navigation and coastal areas.
In particular, among Saturday 17 e Sundaythe focus will shift to the formation of baric lows on the Mediterranean Sea central. These vortices, clearly visible in the model simulations GFSare able to attract cold air from the Balkans, transforming precipitation into neve not just on Alpsbut also along theApennines central at progressively lower altitudes. In short, variability will be the watchword. Let’s not expect a monotonous weather situation, because the volatility of mathematical models suggests that any update could reshuffle the cards on the table. In fact, looking at the projection for the January 27is noted as one powerful high pressure structure over Western Europe can push the disturbances eastward, leaving theItalia in a sort of windy but less rainy limbo.
The unknown of February and the Stratwarming potential
And then there’s the big puzzle of February. Traditionally this is the month when winter shows its sharpest teeth, and this year the eyes of the experts are set on the stratosphere. We often talk about a potential event of Stratwarmingor a sudden warming of the stratosphere above the pole. When this happens, the Polar Vortex can literally shatter, sending masses of freezing air towardsEuropa or North America. However, predicting if and where the post-stratwarming cold will hit is nearly impossible more than two weeks in advance.
At the moment we limit ourselves to observing the signals coming from above, aware that the consequences on the time we will live here on the ground are anything but obvious. It could end in nothing for theItaliaor it could open the doors to a decidedly raw season finale, perhaps coinciding precisely with the days of Merla or the beginning of February. Caution is a must, also because atmospheric dynamics are so interconnected that a small change in one corner of the world can trigger a chain reaction on the other side of the globe. Let’s face it, it’s the usual climate bet we’re now used to.
A fluidity that does not allow certainties
In conclusion, the meteorological evolution of the next two weeks appears extremely complex. If on the one hand it is a cooling of continental Europe is probablethe exact trajectory of Arctic air masses remains the main question mark for theItalia. We will see will it snow in the plains in the North? It’s possible, but we can’t say for sure yet. Will the cold break through decisively towards the South? It all needs to be evaluated, especially considering how the American models seem more inclined to maintain high pressure than the European ones.
What is certain is that we live in an era of meteorological extremismwhere normality has become an almost abstract concept. Mathematical models, however advanced, struggle to interpret such volatile scenarios, where positive thermal anomalies are always around the corner, ready to frustrate any attempt at the return of frost. All we have to do is follow the daily updates, with the awareness that nature always has the last word and that, after all, it is precisely this unpredictability that makes meteorology such a fascinating subject. In fact, today’s analysis tells us that the game between winter and early spring is more open than ever.
Ultimately, maybe it’s for the besta winter that keeps us in suspense, that forces us to look at the sky with renewed curiosity, hoping that, between a rain and a gust of wind, some white flakes may also appear to remind us that, despite everything, the cold season still has something to say. But for now, let’s keep our feet on the ground and our eyes on the maps, waiting for the atmospheric mosaic to fully come together.
Here are the highlights of the worsening of the weather described:
- Arctic irruption: the arrival of polar air will cause a drastic temperature drop, especially at North.
- Snow in Piedmont: significant accumulations expected a Wedge e Aosta between the 17th and 18th Januarywith possible flakes also in theAsti.
- Lombard Alps: heavy snowfall with snow levels decreasing up to 600 metres.
- Impetuous winds: bursts of mistral e southwest up to 100 km/h in Sardinia and storm surges on the Tyrrhenian sectors.
- Instability in the Center: heavy rain and thunderstorms between Tuscany e Lazio.
Credit
(METEOGIORNALE.IT)
