about real winter again :) снова о настоящей зиме

What does mean for you "Mezzogiorno" (Midday)? Is the moment when the sun is in the hiest position onto the sky. What does mean "Mezzonotte" (Midnight)? Exactly controversial - sun locate in the lowest position, other side of the Earth.
il sito www.montagna.tv ha publicato il articolo in versione Italiano:
https://www.montagna.tv/150255/inverno-sugli-8000-parola-a-denis-urubko/ 
Same situation is for the Summer and Winter. The winter's shortest day and longest night is a culmination - Solstice. In this moment the North part or the Globe get minimum energy from the Sun. After that solar rows become stronger every day. So - 22 of December is the middle of winter.

Reading in Wikipedia (https://en.m.wikipedia.org/wiki/Winter_solstice) is:
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"The winter solstice, hiemal solstice or hibernal solstice, also known as MIDWINTER, occurs when one of the Earth's poles has its maximum tilt away from the Sun. It happens twice yearly, once in each hemisphere (Northern and Southern). For that hemisphere, the winter solstice is the day with the shortest period of daylight and longest night of the year, when the Sun is at its lowest daily maximum elevation in the sky.[1] At the pole, there is continuous darkness or twilight around the winter solstice. Its opposite is the summer solstice.
The winter solstice occurs during the hemisphere's winter. In the Northern Hemisphere, this is the December solstice (usually 21 or 22 December) and in the Southern Hemisphere, this is the June solstice (usually 20 or 21 June). Although the winter solstice itself lasts only a moment, the term sometimes refers to the day on which it occurs. Other names are "MIDWINTER", the "extreme of winter" (Dongzhi), or the "shortest day". Traditionally, in many temperate regions, the winter solstice is seen as the MIDDLE OF WINTER, but today in some countries and calendars it is seen as the beginning of winter. In meteorology, winter is reckoned as beginning about three weeks before the winter solstice.[2]
Since prehistory, the winter solstice has been seen as a significant time of year in many cultures, and has been marked by festivals and rituals.[3] It marked the symbolic death and rebirth of the Sun.[4][5][6] The seasonal significance of the winter solstice is in the reversal of the gradual lengthening of nights and shortening of days.
Seasonal lag is the term relating the lag shift between the coldest winter weather and the winter solstice. As latitude increases, midwinter correlates more closely with the winter solstice".
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Similar you can  read in Wikipedia about Summer period. In any languagge.

04 Nov 2019 Alpe Orobie above the level of 1000 m

Photo of Massimo Zucchelli

Inertion? In case you decide to "switch ON" refrigerator into the kitchen - it will take a time to get minimal temperature. In opposite - after "switch OFF" the cold condition will disappear slowly, not escape immediatelly. In same reason the Winter (as a coldest Period of year) start in 01 December - just 21 day before Solstice. And the End of Winter 28(29) February happen 68(69) days after the Solstice.

Snow on the upper pert of Vallseriana 04 Nov 2019

I was looking the Climate diagrams of Meteorologists for the... Milano, as example. Look - the Winter is calculating from 01 December till 28(29) February. For the good visibility I'd prepared this demonstration:
https://youtu.be/WxFO9V9Cnvs

06 Nov 2019 in Valcanale 850 m
Photo of Massimo Zucchelli

My personal expirience about Winter and Spring periods in Karakorum and Himalaya give me exactly same sensation. As example I'd prepared controversial fotos for same points:
https://youtu.be/dhhbyY4Kdow

So, in case you'd like to and understand some of my other thoughts depending for the Real Winter meanings - read it here, please:
http://www.russianclimb.com/urubko_true_winter.html

In this reason all climate (meteorogical) WINTER ascents in Himalayas need to happen in period 01 December - 28(29) February. I am very proud to have successfull expirience on Makalu and G2 already. And hope to repeat same on Broad peak (and K2 perhaps) for the coming winter 2019-2020 with my friends Donald Bowie and Lotta Nakyva.