TASS in its Telegram channel outlines the main theses of the speech of the head of Gazprom, Alexei Miller, at the Russian Energy Week forum. The first sentence looks like this:
“Gazprom predicts an abnormally cold winter for the heating period.”
The following theses are devoted to the energy sector of European countries and the possibilities of Gazprom to supply gas there, so, apparently, the weather forecast in Western and Central Europe is meant.
Long-range weather forecasts are not very reliable. The statement of the scientific-practical conference "Hydrometeorological forecasts and hydrometeorological safety" in 2004 stated :
“The operational models used in large meteorological centers have a predictability limit of 5-7 days and differ from each other in their characteristics, applied numerical procedures, data processing technology and computing power. <…>
Detailed forecasts of meteorological quantities and weather phenomena or a sequence of meteorological systems for a month, for a season and beyond are unreliable. The chaotic nature of the motions in the atmosphere imposes a basic limit of predictability on the order of 10 days for such deterministic forecasts. However, some predictability of mean anomalies in temperature and precipitation exists over a longer period due mainly to interactions between the atmosphere and the ocean and between land and ice. At the same time, compared to the atmosphere, the ocean has been little studied, and therefore further progress in long-term weather forecasting is impossible without intensifying research on regional and global processes in the ocean.”
The Hydrometeorological Center of Russia on its website explains :
“In order to prepare a forecast for a couple of days in advance, you need to have data on the actual weather in an area with a scale of several thousand kilometers. A forecast for a week and beyond already requires information about what is happening with the weather around the globe. In a long-term forecast, one has to consider almost the entire climate system, which includes the atmosphere, the ocean, and the upper layer of the land.
We always know the current state of the atmosphere only approximately, since our observations of the atmosphere are incomplete and inaccurate - the observational network is quite rare and the observational data contain errors. Vast areas of the planet (oceans, high and tropical latitudes) remain poorly illuminated by observational data. On the territory of our country, the density and equipment of the observation network also leave much to be desired. It is possible to increase the density of the network and reduce measurement errors, but not indefinitely - the possibilities for such detail are limited, so our knowledge of the current state of the atmosphere will never be complete. <…>
All this does not mean that we cannot say anything about the future of the atmosphere beyond a couple of weeks. We can, but long-term forecasts are formulated in a different form and the requirements for them are different - as a rule, for long-term forecasts, probabilistic formulation and presentation of results in terms of average values for a period (for example, a month or a season) are used.
It is not clear where Gazprom, which does not have its own meteorological service, got the forecast for an extremely cold winter.
On October 10, the European Center for Medium-Range Weather Forecasts said it was difficult to predict early October winter weather, but early forecasts indicated cold and dry (and wind-friendly) weather in November and December. Director of the Climate Change Service Carlo Buontempo said :
“Models show that early winter in Europe will be dominated by an area of high pressure – the weather will be predominantly dry and very windy. Under these conditions, there is a possibility that easterly winds will lead to lower than usual temperatures.”
At the same time, Buontempo warned that more reliable data on what the upcoming winter in Europe could be like will not be available until three to four weeks later.