January 2021 was cold in Russia – primarily, in the Asian territory where it was among the 15 coldest ones in the entire history of regular meteorological observations in the country since 1891. The weather was abnormally warm in Taimyr, Evenkiya and the north-west of Yakutia in the first decade only, but generally remained cold everywhere from the Urals to the Pacific Ocean during all month, save for the south regions of the Altai and Primorye Territories, the Republic of Buryatia and the Altai Mountains. New temperature minima as low as -55…-60° were recorded in Altai, Chukotka, Yakutia, the Krasnoyarsk Territory, and the Omsk Region. The monthly-averaged air temperature hit the Top Ten of the lowest values in the history of meteorological observations in the north of the Far East, and the Top Twenty, in its south. The anomalies of this temperature reached or exceeded -2…-6° in the Urals and to the east of them.

The thermal footprints were quite different in the European territory of Russia: colder than usual in the second decade (with anomalies down to -4…-8°) but basically warmer in the first and third decades when the monthly-averaged temperatures were 6-8° higher than normal. New records of heat were set in the south of the ETR in the first decade, culminating in Sochi with a new absolute maximum air temperature of 22.4° never observed before in January. In the third decade, daily temperature maxima were recorded in many locations of the Central, North-East and Volga Federal Districts. As a result, the anomalies of monthly-averaged temperatures in the ETR were +2…4° or higher. The weather was warmer than ever on the Arctic Islands of Russia as well. Regarding Russia as a whole, the monthly-averaged air temperature in January was below normal: the last time this occurred was in January 2014.

The monthly-averaged air temperatures in most of Mongolia and in the east of China were above-normal (2-3 or more degrees higher in some places), whereas these figures in the rest of East Asia were close to normal.

In the countries of South-East Asia, the air temperature was close to or less than normal, whereas in India and Pakistan, it was also close to normal but increased in some places: e.g., by 2-3° in Central India.

This January was colder than usual in the south-east of Iran, but the temperature in the rest of the country was either close to normal or increased, by 2-3 or more degrees in the north. The weather in the Near East was noticeably warmer in terms of the normal monthly averages that were exceeded by 2° or more as a rule. The air temperatures never observed in January were recorded all around Turkey. The thermometer readings on the Black Sea coast rose above +30°, but the frozen air which occasionally penetrated there from the north caused their sharp drops. For instance, frosts in Istanbul could be as cold as -15°. At the same time, the temperature in Saudi Arabia was -2°: no such colds had been observed there for the last fifty years.

The weather was very warm in North Africa. The monthly-averaged air temperatures both in the Mediterranean countries in the north and in the countries to the south of Sahara exceeded their normal values by 2-4°. January 2021 became the second warmest in the history of meteorological observations in South Africa, yielding to January 2010 only.

In the countries of Central Asia, this year commenced exactly as the previous year concluded: with very cold weather. The temperatures reached -40° in Kazakhstan (the record-breaking minimum in the country), and -10° in Uzbekistan. The soil in the north of Kazakhstan froze to more than a metre depth. But in the middle of the month, warm air broke through to the west of Kazakhstan and to the republics of Central Asia to set up new air temperature maxima that, at certain locations, persisted for a few days in succession sometimes. The air in the middle of winter warmed up to +15° in Kazakhstan and Kyrgyzstan, to +18° in Tajikistan, to +19° in Uzbekistan, and to +24° in Turkmenistan. On the monthly averages, the air temperature in the Central-Asian countries and in the west of Kazakhstan was 2-3 or more degrees higher than the normal value, but lower than this value in the east of Kazakhstan.

Most of Europe was occupied by abnormally warm weather in January. The monthly-averaged temperature was 2-3° above its normal value in the east of the continent. New temperature maxima were recorded in Ukraine and Belarus, as well as in Greece, Cyprus and Sicily on the Mediterranean coast where the thermometer readings came close to +25°. The situation was completely different in the far west, namely, in Portugal, Spain, Great Britain and Norway. In these countries, January was colder than normal, with unprecedented frosts in Spain reaching -25° in places or as low as -30° in the mountains. New daily temperature minima were recorded in the country; no such colds had been observed by the citizens for almost twenty years. But in the last days of the month, hot air pierced from Africa and created what was later named the "January ardour". The air temperatures rose to +20° in the centre of the country and to +25° or more in the south, and new temperature highs were established.

Heat was raving around North America, most notably in Canada. January 2021 became the warmest in the history of meteorological observations in the latter country, with the previous achievement surpassed by 0.5° straight away. The monthly-averaged temperatures were 4-8 or more degrees higher than usual all over the country. The weather was also abnormally warm in the USA, in Mexico and in Central America where the normal values were exceeded by 2-6°, 2-3° and 1-2°, respectively. In the US, the monthly-averaged air temperature entered the Top Ten of highest values recorded since 1891.

The air temperature in January averaged over the Northern Hemisphere turned out to be the fourth warmest since 1891 to an accuracy of 0.1°.

In Moscow, the monthly-averaged temperature of January was -5.8°, corresponding to the anomaly of +3.5°. A number of new daily temperature maxima were recorded.

La Niña (cold episode of the Southern Oscillation) in the Pacific Ocean remained strong in January. The negative SST anomalies in the La Niña zone reduced compared to the previous month, but the area occupied by them expanded significantly, reaching 20°N in the Northern Hemisphere and as far as the coast of Chile in the Southern Hemisphere. This being the case, high negative anomalies (in excess of 1°) were generally located in the Southern Hemisphere. At the same time, the subtropical latitudes of the Pacific Ocean in the Northern Hemisphere were occupied by high positive ones up to +1…2° or more which spread to the equator in the west. As for the middle latitudes, the water was abnormally cold in the Sea of Okhotsk and to the east of it. The average SST anomaly in the Pacific Ocean decreased since the end of the previous year.

In the Atlantic Ocean, the latter value remained about the same. The ocean surface along the Gulf Stream was very heated. The SST anomalies in the west of the Ocean were higher than +2…3° at the latitudes from 30°N to 50°N, but the water farther on between Greenland and Europe was abnormally cold. The SST in the marginal European seas, viz., the Mediterranean, Black, North and Baltic Seas, was higher than normal.

Most of the ETR received a lot of precipitation: for example, its normal rates in the North-West, Central and Volga Federal Districts were exceeded by 2.0-2.5 times in places. Heavy snowfalls came to Chuvashia, Tatarstan, and to Nizhni Novgorod, Penza and Ulyanovsk Regions in the middle of the month and brought up to 20 mm of precipitation per day. New daily precipitation totals were recorded in Tatarstan and in Kirov, Saratov and Ryazan Regions. The daily amounts of snow mixed with rain and sleet reached 50 mm in the Krasnodar Territory and 65 mm in Karachay-Cherkessia. By the end of the month, the thickness of the snow blanket was up to 20 cm, or as much as one and a half to two metres in the foothills of Caucasus. The North Caucasian Federal District and parts of the Stavropol Territory and Astrakhan Region were the only areas where the monthly precipitation was less than half of the normal figure.

In the Urals, the precipitation amounts were normal or somewhere increased in the south, but quite small (less than 50% of the normal value) in the north. In Siberia, they were basically fair, or even excessive in the south of the Krasnoyarsk Territory and in the Irkutsk Region: 2-3 times the normal value in places. Such abundance of precipitation preserved further eastwards in the south regions of the Far East Federal District where the normal values were also exceeded by about 2-3 times in the Republic of Buryatia, the Trans-Baikal Territory and the Amur Region. The same picture was observed in certain locations of Primorye and Kamchatka. Yet in most of Yakutia, Kolyma and Chukotka, and of the Khabarovsk Territory, precipitation was lacking, and amounted to less than 50% of the normal quantities.

Precipitation was scarce in the east of China and in Korea, but roughly normal in Japan. Heavy snowfalls took place along the coast of the Sea of Japan at the beginning of the month.

Intensive showers swept across the countries of South-East Asia and caused large-scale floods in Malaysia, Thailand, Indonesia and the Philippines. The depth of flood waters in some regions reached three metres. The river floods and landslides affected hundreds of thousands of people and led to fatalities.

The weather in South Asia was dry. In India, only the state of Tamiland in the south was hit by rains – and very heavy ones indeed: more than 100 mm of rainwater could accumulate there per one day. Such powerful showers had not been observed since 1915 in this part of the country. In the neighbouring Republic of Sri Lanka, 140 mm of precipitation was brought by rains in two days. The month in Pakistan was dry everywhere apart from the north where the amounts of precipitation were normal.

In the Near and Middle East, precipitation was lacking for the most part, but occasional heavy rains did take place nevertheless. In Israel, Syria and southern Turkey, they caused floods in the middle of the month. Residents of Saudi Arabia and Yemen could see snow lying here and there. In Georgia, 60 to 90 mm of precipitation accumulated daily in different regions.

In North Africa, the weather was dry as it should considering the climate in the region, with the exception of heavy downpours that caused flooding in Morocco at the beginning of the month. The tangerine plantations in Algeria and Morocco were covered with snow. In some places, the depth of freshly fallen snow exceeded 30 cm.

Scarce precipitation was observed in Central Asia: less than half of the normal amount as a rule, or less than its quarter in many locations.

Europe was inundated with rains and piled with snow in January. The normal precipitation rates in many countries were exceeded by 1.5-2.0 or more times. Up to 30 mm of mixed precipitation fell per day in some places. In Spain, January snowfalls of this year have been recognised as the heaviest in the past ten years. White flakes have even been observed on the Canary Islands. Heavy snowfalls took place in the north of Italy and in Austria, and torrential rains that hit Switzerland caused flooding in the country. Snowfalls in England and Scotland created a snow cover up to 30 cm deep. The weather in the east of the continent (the Balkan countries, Moldova, Ukraine and Belarus) was also remarkable for heavy rains and snowfalls. New daily maxima of precipitation were recorded in a number of locations.

The main amounts of precipitation in the USA came to the central, southern and western regions of the country. There, the normal rates were exceeded by 1.5-2.0 in places. Pelting rains in the north-west states of Oregon and Washington produced mudflows. A snow cyclone in the middle of the month broke through far to the south of the country and covered Texas, Louisiana, Alabama and Mississippi with snow completely. At the end of the month, a snow storm hit Illinois. At the same time, rains were falling in California, and snowfalls in the Sierra Nevada mountains were piling snowdrifts that reached three metres in height. The precipitation amounts were normal or increased in the central regions of Canada, but less than normal on the coasts. The weather in the north of Mexico was rainy.

In Moscow, 68 mm of precipitation fell; this is 162% of the normal amount.