Unstable atmospheric phenomena could even cause a tornado
Moscow was attacked by a tornado on June 6. This was reported by the telegram channel “What’s there in Moscow”. The whirlwind, according to bloggers, swept over the Kaluga highway at about 6 pm in the form of a dark trunk hanging from a cloud, but not reaching the ground. Roman Vilfand, scientific director of the Hydrometeorological Center of the Russian Federation, told MK that the unstable phenomena observed this week in the atmosphere could theoretically contribute to the formation of strong vortices over the city.
According to the weather forecaster, Moscow is currently experiencing very strong instability in the atmosphere, which is intensified by the sun's rays, which have colossal energy in the run-up to the summer solstice, which will occur on June 21.
“We issued a storm warning for Thursday, June 6: from 12 noon until the end of the day, very heavy rain, thunderstorms, hail, and winds of up to 20 meters per second were predicted,” says Roman Mendelevich. – The word “very” always denotes a dangerous phenomenon. In this case, we were talking about a large amount of precipitation exceeding the threshold value. After such events, threats to the functioning of the city arise in the form of floods of water and poor visibility on the roads.
According to Vilfand, the same cyclone greatly surprised meteorologists on June 5: at about 10 o’clock an amount of precipitation unprecedented in the history of meteorological observations in the capital fell . At the VDNH station, more than 45 millimeters of precipitation was recorded in 20 minutes.
“Such downpours don’t always happen even in the tropics,” says the scientist. – But ours was local, on a scale of several kilometers. For example, in the area of the Ostankino Tower at the same time there was only 20 mm, the Balchug station generally recorded only 3 mm, and in Sheremetyevo — not a drop. Here's Moscow for you!
The city is now under the influence of a low pressure trough. What does it mean? Air masses move vertically, from the surface of the earth upward. But since the cloudiness is not continuous, an additional effect arises for the rise of air masses: the sun bakes the soil, but not everywhere. For example, in peat bogs, heating of the underlying surface occurs very quickly, causing warm, light air to rapidly rise upward. This is called explosive convection. Then, according to the laws of physics, condensation of water vapor occurs, rapid cloud formation and heavy rains.
Convection processes and heating of the underlying surface, according to the forecaster, were joined this week by a third factor: frontal sections passing through the center , so-called secondary fronts, which further enhance convection.
“When three factors come together, phenomena associated with very heavy and local rains arise,” says Vilfand.
“I still need to check the information about tornado. But in principle, it is possible given the factors mentioned above. Its formation may also be due to the fact that air masses, due to fragmented cloudiness, warm the territory unevenly.