Italy, like a large part of Central Europe, Balkan and the Iberian Peninsula, is found in the middle of anintense heat wave which is bringing very high temperatures, too 10-15 ° C above average of August, and numerous fires in Spain, in the south of France, in the Balkans and in southern Italy (like the recent fire on Vesuvius). In Italy we have peaks that approach the 40 ° Cwith a very intense heat and a suffocating ace.
The manager of this situation is one heat dome (Heat Dome in English), an absolutely typical phenomenon in this period of the year which consists of a vast High pressure figure that traps and compresses hot air of African origin. Often in journalistic language we tend to speak of “heat dome” as synonymous with “heat wave”, but they are two distinct phenomena and not all heat waves are caused by domes.
What is a heat dome and how the one that is bringing the heat to Europe has formed
A heat dome It is that phenomenon for which a mass of hot air – sometimes coming from lower latitudes – remains “trapped” due to the high surrounding pressure, which “crushes” the hot air pushing it down and warming it even more. It is a rather stable condition that it can also last for several days or even weeksbecause as the name suggests it is a substantially “dome” isolated from general circulation of air currents, deviated by a persistent high pressure situation.
The heat of these days is due to the fact that a heat dome has been created on central-southern Europe that is trapped hot air transported by the advancement of a promontory of Saharan originthat is, an extension of the North African anticyclone.
The hot air arrives on Europe with the anticyclonic circulation after collecting large quantities of water vapor produced by the evaporation of a Mediterranean already in itself very hot. At this point he meets a baric figure who keeps her in place, making her accumulate: her high temperature leads her to expand upwards, but but The high pressure at altitude resists it downwards. The column of hot air compresses and, like every gas, compressing itself he warms up. So here the temperatures rise significantly thus causing the strong heat wave of these days. If we add the humidity collected above the Mediterranean to this, apfas conditions are created that increase the temperatures perceived.
This happens in both hemispheres and tends to happen more frequently in the height of summer, when the meteorological configuration is more stable. In these days, for example, the heat dome on Europe is made stable by the fact that it is found “Cooked” between two low pressure regionsone to the east above Russia and one west on the Atlantic Ocean.
Forecasts for the next few days in Europe and Italy
At the moment the heat dome extends from the Iberian peninsula to the Balkan region, with the center between France, Germany and the Alpine area. According to the predictions of the meteorological models, from the mid-week the configuration will gradually move to the north-east, with the center in Poland over the weekend. Temperatures can also arrive 8-10 ° C above the average of the periodwith tips up to 43-44 ° C in Spain e 40-41 ° C in Italy provided in Tuscany and in some areas of the North-West. In our country the intense heat will last At least until Sundaybut in the next few days some heat thunderstorms will be possible especially in the hottest regions.
