MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHERN HEMISPHERE AS OF MAY 2025
Air temperature
Cold weather that came to the ETR at the end of April remained cold in the ETR for the first and second decades of May, with the decade-averaged temperature anomalies reaching -3…-5°. In the Yaroslavl, Moscow, Ryazan, Tver, Tula, Ivanovo and Bryansk Regions, the thermometer columns dropped below zero, and new daily temperature minima were recorded – notably, for several days in a row in some places. Warmth arrived in the third decade only when the decade-averaged temperature anomalies became +2…6° all the way from the Kola Peninsula to the lower reaches of Volga. In the Russian North, new temperature maxima in excess of +25-30° were recorded.
In the Urals, abnormal heat in the first decade changed to normal weather in the second, and to the cold one in the third – with the decade-averaged temperature anomalies down to -2…-3°.
The weather in Siberia was noticeably warmer than usual in the first decade when new air temperature maxima were even measured in the north of the Krasnoyarsk Territory. Abnormal heat in the second decade solely preserved in the north, while the temperatures in the south were approximately normal. In the third decade, cold in the west came along with heat anomalies in the east of the region where the thermometer readings rose to +30-35° in the Krasnoyarsk Territory.
MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHERN HEMISPHERE AS OF APRIL 2025
The first days of April still brought new records of heat to the ETR. Daily maxima of air temperature were recorded on the Volga, in the Cis-Urals and in the Southern Urals, driving the thermometers to the values close to +25° in a number of places. But by the middle of the first decade, frosts came there again to replace the records of heat with those of cold, and the average air temperature in the first decade turned out to be subnormal in the central and southern regions of the ETR.
At the beginning of the second decade, cold weather with new record-breaking minima of air temperature still persisted in the north-west, e.g., in the Pskov, Leningrad and Arkhangelsk Regions and in the Republic of Karelia, but in mid-April, the unprecedented warmth arrived there with new record-breaking temperature maxima in numerous locations. April in the ETR ended up with yet one arrival of cold weather, and frosts or even record colds spread to the very south – Crimea, the Volgograd, Rostov and Astrakhan Regions, and Kalmykia.
In most of the territory beyond the Urals, the weather in April was warmer than usual; in the north-east, extreme heat persisted for most of the month. In mid-April, record high temperatures above +30° were observed from Omsk to Irkutsk in the south of Siberia: such thermometer readings were only measured there in summer of select years before. The month concluded with record high temperatures in the north of the Krasnoyarsk Territory, in Evenkiya and Yakutia.