MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHERN HEMISPHERE AS OF DECEMBER 2025 

Air Temperature

In Russia, temperature trends did not essentially change in December: their general markers were cold anomalies in Siberia and Yakutia, and warm anomalies west and east of this seat. Frosts in Yakutia, Evenkiya and the north of the Krasnoyarsk Territory were -50…-55° or below. Very cold spells down to -35° were also recorded in the Russian North. Moreover, while the average anomalies did not fall below -2…-4° in the first decade, they reached as cold as -6…-10° in the second one. At the same time, abnormal warmth spread across the ETR and the north of the Far East, with new daily maxima of air temperature in the north-west and north of the ETR as well as in Kolyma, Chukotka and Kamchatka.

In terms of final monthly averages, a huge area of cold anomalies extended from the north-eastern ETR regions throughout the Northern Urals, most of Siberia and Yakutia and the entire Trans-Baikal: there, the monthly-averaged air temperature was 2-8° below normal. However, the weather in December was about 2° warmer than usual in most of the ETR, in the south of the Urals and of Western Siberia, 2-12° warmer in the north-east of the country. In the Central Federal District, this December closed the top ten warmest in the history of meteorological observations since 1891, but in the rest of Russia, it was far from such feats.

As to the entire 2025, the picture was completely different: alongside 2024, this year in Russia was the second warmest in the meteorological chronicle, with the leading position still awarded to 2020 when the average air temperature in Russia exceeded 0° only once in the history of regular meteorological observations. All of the ETR as well as the Volga region and the Central Federal District separately received a record-breaking amount of heat in 2025 and enjoyed the ever-high annual air temperature. The North-Western and Central Federal Districts were ranked the second warmest in the ranking list, while the Southern and Siberian ones, the third warmest.

The average air temperature in 2025 was above-normal almost everywhere in Russia, with the exception of Chukotka where annual temperature anomalies were weakly-negative. It was 1° higher than normal in the ETR, in the Urals, in Siberia and in the Primorye, on Sakhalin and in Kamchatka, and 2° higher in the Volga region and partly in the Russian North. In the Arctic, anomalies were even higher, +3 or more degrees in the Novaya Zemlya and on the archipelagos of the Barents and Kara Seas.

In Moscow, the average December temperature was -1.2°, which is a +3.2° anomaly. This December was the tenth warmest in the meteorological annals of the capital, and this year as a whole, the record-breaking warm.

The average temperature in the Northern Hemisphere was ranked the fourth to fifth highest since 1891, yielding to Decembers 2023, 2024 and 2015.

In Mongolia and the northern provinces of China, December was slightly colder than usual, but in the central, southern and western regions of the latter country, it was 2-3 or more degrees warmer than the normal value. In the rest of the country and in neighbouring Korea and Japan, this value was a bit exceeded. In China, December 2025 was the second warmest in the history of observations.

The temperatures in the countries of South-East and South Asia were close to normal against the background of weakly-positive anomalies, with the exception of the central regions of India where these anomalies were weakly-negative.

Similar trends were observed in the Near and Middle East.

In the countries of Central Asia, the weather was noticeably warmer than usual: the normal values in all republics were overridden by 2-3° or more. The frosts in the north of Kazakhstan reached -20…-30° on some days.

In North Africa where the monthly-averaged temperatures in December were close to the normal ones, the territories of Niger and Chad were outstanding: there, the weather was two to three or more degrees warmer than normal.

Record-breaking warmth visited the east and north of the European continent, with new maxima of air temperature in Belarus, in the Baltic countries and in Finland: the monthly-averaged temperatures of December in these countries, as well as in those of Central Europe and Scandinavia, were two to three or more degrees higher than their normal values. Throughout the rest of the continent, the temperature conditions were near-normal.

December temperature averages in the North-American continent sharply contrasted with each other. While the month turned out to be notably warmer than usual almost in the entire Canada, in Alaska and in the north-east of the USA, and the average air temperature was 4-8° lower than normal in the west of Canada and in Alaska or more than two degrees lower in the Atlantic coast of the US, this December was 2-4 or more degrees warmer than usual in the western United States and in the north of Mexico where new temperature maxima were recorded. Alaska has not seen such a cold December since 1974, i.e., for more than fifty years.

Regarding the Northern Hemisphere, the average temperature of 2025 reproduced the previous achievement dated 2023 to an accuracy of 0.1°C and, together with 2023, was called the second to third warmest in the history of regular meteorological observations since 1891, with the record still held by 2024. On all continents of the Northern Hemisphere except for certain territories of India, the average annual air temperature was above normal: one or more degrees above in North Africa, Western Europe, the most of the Asian continent, the north of Canada, the west of the USA and the north of Mexico, two or more degrees above in the Arctic Canadian islands, the north-west of Kazakhstan and a number of already mentioned Russian areas, and three or more degrees in excess of the annual normal value in some regions of the Arctic. In the history of meteorological observations, the year 2025 was the record warmest in the UK, the second warmest in China, Finland and Ireland, and the third warmest in the Arctic and in Japan. 

 

 

Sea Surface Temperature

 

Weak negative anomalies attesting that the neutral phase of the Southern Oscillation continued were still observed in the equatorial Pacific of the Northern Hemisphere. Most of the Ocean area in the Hemisphere was occupied by positive anomalies that exceeded one to two degrees in the tropical zone. Apart from the equator, weak negative anomalies were observed in the region of the Sea of Okhotsk, off the coast of Alaska, and in the east of Japan. The average SST in the Northern Hemisphere was above-normal traditionally already, and was rated the third highest according to the ranking list of observations.

This December, the average SST of the Atlantic Ocean in the Northern Hemisphere was significantly lower than in the same month of the previous years, although SST anomalies were also positive in most of its water area, with those higher than +1° located in the tropical zone, as well as off the coast of Greenland and Scandinavia, and in the Barents Sea in the north. The SST of the Mediterranean and Black Seas was significantly higher than normal.

 

 

Precipitation

 

Almost everywhere in the ETR, precipitation reached the normal figures in December, and was only sub-normal in some entities of the Southern Federal District (the Volgograd and Astrakhan Regions and the Republic of Kalmykia) and in the Luhansk and Donetsk Republics. And in a number of regions, the normal amounts were exceeded by 1.5 times, i.e., in the Murmansk Region, the Perm and Krasnoyarsk Territories, and the Republics of Udmurtia and Adygea.

At the beginning of the month, heavy snowfalls occurred in the Murmansk Region and in Karelia, and at the same time, heavy showers took place in the Black Sea coast of the Caucasus where up to 50 mm of rainwater fell in one day or in a day and a half. In the middle of the month, snowfalls swept across the Central Russia and set new highs of daily precipitation.

In the Ural Federal District, the precipitation amounts were 1.5 or more times greater than normal.

In Siberia, with the exception of Taimyr in the north and Khakassia in the south, precipitation was normal or higher than that. Heavy snowfalls passed in the Krasnoyarsk Territory, in the Kemerovo Region and in Altai, bringing up to 10-15 of atmospheric moisture daily to some locations.

In the Far East, snow and rain were abundant, especially in Kolyma and Kamchatka where the normal monthly amounts were exceeded by two to three or more times, but also in the Amur Region and the Jewish Autonomous District where 10-40 mm of atmospheric moisture accumulated per day, with new daily maxima in place. Precipitation in Chukotka and Primorye was subnormal.

As to the annual totals, they were normal almost in the entire territory of Russia. A shortage of precipitation was only observed in Donbass and in some areas of the Arctic region.

In China, more than 1.5 times the normal monthly amount in December went to the eastern coast of the country, to the areas along the border with Mongolia, and to the north-western territories. In the rest of China, precipitation was lacking, and on the Korean Peninsula and in Japan, close to normal.

The weather in most of South-East Asia was dry: rains fell in certain places only, most notably in Indonesia, as in the previous month.

In South Asia, a shortage of precipitation was also observed, with rains in some spots of India and heavy rains in Sri Lanka only.

Substantial precipitation was measured in the Near East. In Saudi Arabia, snowfall in the deserts was the heaviest in thirty years. At the same time, heavy rain fell in the neighbouring countries, and floods were reported. Iran experienced the most severe drought in the past scores of years.

Rains inundated the countries of Central Asia, with new precipitation maxima in Uzbekistan where rain was replaced by snowfall in some places, as in neighbouring Kazakhstan.

In North Africa, sufficient precipitation was only brought to the coastal areas of the Mediterranean Sea and the Gulf of Guinea resulting in the monthly totals 1.5-2.0 or more times the normal figures. In Morocco, heavy rains were reported to cause floods in the western part of the country. The republic of Somalia was suffering from a severe drought for more than five years already.

The weather in most of Europe was dry. Normal precipitation was only allotted to the Scandinavian countries in the north and to the Baltic countries, to Belarus and parts of Ukraine, as well as to Spain and Portugal in the west.

In Canada, normal precipitation was observed in the north of the country and in Quebec. In the USA, the precipitation patterns were similar; there, the western and north-eastern parts of the country were wet, and the rest territory was still dry. Torrential rains led to flooding in California where in some locations they fell for several days almost without interruption.

The annual precipitation totals were normal in most of the Northern Hemisphere, and notably higher than that in India, Pakistan, in the countries of South-East Asia, in the east of China, in the west of Middle Asia and, partially, in the African coast of the Mediterranean Sea. A precipitation shortage in the annual terms was observed in the Near and Middle East, in most of Central Asia, in North Africa, in Canada and in some European countries.

In Moscow, the precipitation total in December was 46 mm, or 90% of the normal value. The year in the capital resulted in 735 mm of atmospheric moisture, which is within the normal limits.

 

Hydrometcentre of Russia