Air Temperature

The whole month in the ETR was abnormally cold. In each of the three decades, there were areas of decade-averaged temperatures 2-4° lower than normal, and in the first decade, five or more degrees lower. New daily temperature minima were recorded everywhere from the Volgograd Region to the Lower Volga, and the resulting monthly averages turned out to be 2-3 or more degrees below the normal values in the Central, Volga and Southern Federal Districts. The last time such a cold May was logged by the statisticians some twenty years ago in 1999-2002, though in the Volga region, May 2017 was also very cold. But in the last days of the month, the record-breaking heat came to the north and south of the ETR, and new temperature maxima were measured in the Arkhangelsk Region as well as in the Krasnodar and Stavropol Territories.
In contrast to the ETR, the weather in the Urals and in Siberia was mostly warm or even hot from time to time. In the history of meteorological observations, this May was the second warmest in Siberia, yielding to May 2020 only, and the fourth warmest in the Urals where the monthly-averaged air temperatures were 4-8° higher than normal, and the decade-averaged ones, 6-12° higher in the second and third decades. Numerous daily temperature maxima were set all the way from Taimyr to Altai, Khakassia and the south of the Krasnoyarsk Territory.
In the Far East, above-normal temperatures were recorded in the north of the region only (in Chukotka, Kolyma and northern Yakutia), accompanied with new temperature maxima. Meanwhile, the temperature background in the south was normal. As a result, the monthly-averaged air temperature turned out to be 2-4° higher than normal in the north, and close to normal in the south, even at a negative background in some places.

Air Temperature
From the first days of April, the southern regions of the ETR were in possession of extreme heat. At times, the thermometer readings rose above 25-30° to result in new daily temperature maxima. The air temperatures averaged for the first decade were 3-5° higher than normal in the south of the ETR, and close to normal in the northern and partly the central regions only. But in the second decade, abnormal heat came to the Russian North as well, with new air temperature maxima in the Arctic. And finally, the whole picture dramatically changed in the third decade. The heat survived in the south only where temperature maxima in excess of +30° were established again in the Volgograd and Astrakhan Regions as well as in the Krasnodar Territory and in the North Caucasus, whereas the weather in the northern and central regions became noticeably colder. The thermometer readings in the Moscow, Oryol, Belgorod, Kursk, Tambov and Lipetsk Regions and in the Volga region would drop to -3…-5° and below at night, and the temperature averages for the third decade turned out to be normal or even 1-2° lower than that.
Similar to the ETR, the first two decades in the Urals were warm. In the second decade, new temperature maxima were recorded in the Southern Urals and in neighbouring Bashkiria, the air temperatures rising above +25° sometimes. In the third decade, similar to the ETR again, colds came to this area, and temperatures below -5° were observed in Bashkiria and in the Chelyabinsk, Kurgan and Sverdlovsk Regions.