MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHERN HEMISPHERE AS OF MAY 2026

Air temperature 

With the beginning of May, cold weather left the ETR, and the temperatures became normal, or even two or more degrees warmer in the Central Federal District. New daily maxima of air temperature were recorded in the Ryazan, Tula, Smolensk, Bryansk and Orel Regions, in the south of the Moscow Region, and in the neighbouring Pskov and Nizhny Novgorod Regions. In the second decade, the heat flow increased and spread over the entire Russian Plain. The decade-averaged temperature anomalies reached +3-4°, or +5-6° and higher in the north, and new daily temperature maxima were measured again, now in the Upper and Middle Volga regions, as well as in the north: in the Arkhangelsk and Vologda Regions, in the Komi Republic, and in the Nenets Autonomous region. In the third decade, high positive anomalies survived in the Russian North and in the north of the Central and Volga Federal Districts only, while the weather in the rest of the ETR turned cool, with the decade-averaged air temperatures up to 1.5° lower than their normal values in some places.

In the Urals, the weather was abnormally warm for almost the entire month, with new air temperature maxima recorded, and the average air temperature was two to three or more degrees higher than normal in each decade.

In Siberia, abnormally warm weather persisted throughout the first decade of May (with anomalies of +3-4° or greater), and new air temperature maxima were also recorded. Yet in the second half of the month, everything changed: the warmth still retaining in Taimyr and its nearby regions in the second decade gave way to the colds, and the decade-averaged air temperatures turned out to be 2-3° less than normal in many entities of the Federation in this Federal District.

In the Far East, the temperature trends were generally close to normal. Only in Kolyma in the second and third decade, as well as in the Amur Region and the south of Primorye in the third decade, the average temperatures were 2° higher than usual. In the mid-May, the weather in the east of Yakutia and the north of the Khabarovsk Territory was noticeably colder than normal.

Such distribution of heat and cold resulted that this month became the last among the top five warmest Mays in the historical chronicle of Russia since 1891, with May 2020 remaining the all-time warmest. May 2026 was the fifth warmest in the ETR, in the bottom of the top ten warmest in the Asian Territory of Russia alongside May 2025, and the third warmest in the North-West Federal District.

The monthly-averaged temperature was 2-4° above normal in the Russian North, the Volga region, the Urals and partly the north-east of the country, and about normal in the rest of Russia or slightly subnormal in the southern ETR and in parts of Siberia and Yakutia.

May marked the end of the spring season with very warm weather in the entire ETR save for the Krasnodar Territory, and in the Far East where normal air temperatures for spring were overridden by 2-4 or more degrees. This spring, the weather was colder than usual in Siberia and the eastern Urals: there, the average temperatures were 1-2° less than normal. The spring in Russia was at the end of the top ten warmest in the meteorological annals of the country since 1891, very warm in the ETR (colder than the record-breaking spring 1995 only), the ever warmest in the Russian North, and the second to third warmest in the Far East.

This May, the temperature averages in the countries of East Asia were close to normal, with weakly positive anomalies for the most part, or weakly negative ones in the west of China. The temperature on the Korean Peninsula and Japan islands was one or more degrees higher than normal in some places.

Approximately normal value of the monthly-averaged air temperature was reached in the South-East Asian countries; in Vietnam, this value was exceeded by some 1.0-1.5°.

The air temperature in India was normal, similar to most of Pakistan, where in some places it was 1-2° higher.

The temperature in Iran was also normal or slightly increased in places, while the Near East was starving for heat in May: on the monthly average, the weather during the month in Turkey, in the North Caucasus and Levant countries and in Israel was notably colder than usual, with monthly-averaged temperature anomalies of -1..-2°.

Very warm weather dominated in Central Asia where the monthly-averaged air temperature in Kazakhstan, Uzbekistan and Kyrgyzstan exceeded the normal value by 1-2 or more degrees, and anomalies in some regions were higher than 3°.

Temperatures in most of North Africa were normal, at the background of small positive anomalies as a rule. But in the north of Algeria and Egypt, and in the countries bordering the Guinea Gulf, the sign of those anomalies changed to negative in places.

This May was very warm in Europe: numerous new temperature maxima were recorded in Italy, France, the UK, and Ireland. At the end of the month, the weather was already as hot as in summer, and the air temperature exceeded +30°. The UK Met Office reported that May 25, 2026, became the hottest May day in the country, and that a new temperature high for May was now +34.8°. Across all Europe, the average temperature in May was above-normal, +2 or more degrees above in France, England and Spain. This May entered the top five warmest in the meteorological history of the continent.

In the North American continent, the monthly-averaged temperature was about normal; in northern Canada, some 2° higher than that. Anomalies in the USA were negative south of the Great Lakes and in Alaska.

The air temperature in May averaged over the entire Arctic was approximately 1.5° higher than normal.

The average air temperature of the month in the Northern Hemisphere calculated to an accuracy of 0.1°C occupied the second line of the highest values in the history of meteorological observations since 1891 (along with 2025 and 2020 years), with May 2024 remaining the leader.

The average air temperature in spring 2026 in the Northern Hemisphere was among the top five of highest in history. It was 1-3° above normal in Europe and Central Asia, in the Middle East, in the countries of East and South-East Asia, in the US, in Mexico, and in the north-eastern Africa. But in the north of the American continent (in Canada and in Alaska), spring was noticeably colder than usual: its average temperature was 1-3° below normal. In the US, China and Europe, this spring was the second warmest in the observation history. At the same time, no such a cold spring had been seen in Alaska for half a century since 1972.

In Moscow, the average air temperature in May was +15.5°, with an anomaly of +1.9°. This spring in the capital was very warm, the third warmest in the ranking list since 1891 along with the springs of 2025 and 2007. The spring of 1975 in Moscow was the warmest on record.

 

Sea surface temperature

 

In the Pacific Ocean, new El Niño came into force in May 2026. The monthly-averaged SST anomalies became higher than +1° east of 110W in the equatorial zone, higher than +1.5° east of 95W, and higher than +2.0 off the coast of America. All at once, the development of El Niño affected the general SST background of the Ocean. SST anomalies from the longitudes east of 160E to as far as the Mexican coast exceeded +1-3°. Other water bodies with equally high anomalies were located off the coast of Asia in the East-China, Yellow and Japan Seas, off the Pacific coast of Japan and in the western part of the Sea of Okhotsk. Almost all the rest of the Pacific water body in the Northern Hemisphere was also heated to above-normal temperatures, except for the water off the coast of Alaska. The average SST of the Pacific Ocean in the Northern Hemisphere reached its absolute maximum for May.

High positive SST anomalies were observed in the Atlantic Ocean as well, where they occupied a water area from the Gulf of Mexico and the Caribbean Sea eastwards to the central part of the Ocean, and amounted to +1…2 or more degrees. Comparable anomalies were measured off the coast of Western Europe, as well as in the Greenland and Barents Seas. The SST values off the US coast on the other side of the Ocean were subnormal, as in the Black Sea or in the east of the Mediterranean Sea.

 

Precipitation

 

This May in Russia was rich in atmospheric moisture. In the ETR, the most prominent contributors were the South and North-Caucasian Federal Districts. On several occasions during the month, meteorological stations reported up to 20 mm of precipitation per day. The accumulated monthly totals were twice above normal in the Krasnodar and Stavropol Territories as well as in the Chechen Republic, and 1.5 or more times above normal in the Astrakhan Region and in the Republics of Kalmykia, Adygea, Dagestan, North Ossetia, Karachay-Cherkessia and Crimea. Another ETR region of high precipitation was the North-West Federal District where up to 15-20 mm of rainwater per day fell in some places. The total figures were two times higher than normal in the Kaliningrad Region and 1.5 times higher in the Arkhangelsk and Murmansk Regions as well as in the Republic of Karelia. Given all these large and moderate rainfall quantities in the ETR in May, precipitation shortage was still observed in some constituent entities of the Federation, namely, in the Belgorod Region in the Central Federal District, the Samara Region and the Republics of Tatarstan and Bashkortostan in the Volga Federal District, as well as in the Luhansk Region.

Precipitation in the Urals was approximately normal, albeit that slightly increased in their southern part (in the Kurgan and Tyumen Regions). In the latter Region, the record-breaking daily precipitation totals were even recorded. In the north, snowstorms were observed in the Khanty-Mansi Autonomous District.

New snowfalls were also registered in Evenkiya: in places, they were exceptionally powerful, and added up to 15-20 cm of new snow cover. Mixed snow and rain was observed in southern Siberia (in the Novosibirsk and Kemerovo Regions, in the Altai Territory, as well as in the Republics of Tyva and Khakassia). In Tyva, the normal monthly precipitation amount was surpassed by almost three times, while in the Novosibirsk Region, it was exceeded by 1.5 times. In the rest of Siberia, precipitation was normal practically everywhere.

No precipitation was brought to many regions of the Far East for most of the month. In terms of the monthly totals, precipitation was lacking in the Chukotka Autonomous District, in the Khabarovsk and Primorye Territories, in the Amur Region and in the Jewish Autonomous Region. The Kamchatka Territory received above-normal precipitation.

It is well-known that spring precipitation determines the productivity of agricultural plants in many ways. This spring, precipitation was abundant almost everywhere in Russia. Among the regions where it was comparatively insufficient were certain regions of the South-West and Central Federal Districts, the Amur Region, the south of the Khabarovsk Territory, as well as Chukotka.

In Moscow, the precipitation total in May amounted to 83 mm, or 136% of the normal value. During the spring, 195 mm of precipitation fell, equal to 1.4 times the normal figure. This spring was the eighth wettest in the meteorological chronicle of the capital where the highest value equal to 244 mm was observed in the spring of 1976.

China was deluged with rains: their monthly amounts in the east and north-east of the country were 2-4 times larger than normal. As of the rest Chinese territory, precipitation was normal, and was deficient in the north-west only. Precipitation was also normal on the Korean Peninsula and in Japan.

Atmospheric moisture in the countries of South-East Asia was either normal, or above-normal: in some regions of Vietnam and Thailand, up to 1.5 times the normal figure.

The weather in most of India was dry, but with torrential rains in the east and north-east of the country where the normal monthly rainwater amounts were exceeded by 1.5-2.0 times. A similar picture was also observed in neighbouring Bangladesh. In Pakistan, the weather was generally dry.

In Central Asia, this May was rainy: the daily precipitation totals in Uzbekistan and Tajikistan reached 20-40 mm, and new maxima of precipitation totals were recorded. Abundant rains caused river flooding. The monthly-averaged precipitation amounts in most Central Asia republics were 2-4 times above normal. Meanwhile, the weather was dry in Kazakhstan, except for its western regions.

Rains inundated the Near and Middle East, and led to flooding in a number of regions. Snow fell in the mountains of Turkey and the Levant countries.

The weather was dry in most of North Africa, with the rain solely observed in the north-west (in Morocco and Algeria) and the south (in the countries of the Gulf of Guinea); there, precipitation was normal, or above-normal in places.

In Europe, precipitation was ample in the west of the continent, exceeding the normal monthly totals by 1.5-2.0 times in some places in Italy, Germany and France. At the same time, dry weather reigned on the Iberian Peninsula and in the UK. In the north, the weather was also dry in the Scandinavian countries, while in the east of the continent, precipitation was normal in Belarus and the Balkans, and scarce in Ukraine.

Most of Canada received meagre atmospheric moisture; its normal amount was measured along the Atlantic coast and in the Great Lakes region. But the quantity of precipitation was huge in the western province of Yukon, where it was 2-3 times greater than normal. The US state of Alaska received the same precipitation amount. In the rest of the USA, precipitation was insufficient in the west of the country and normal in its states located on the Atlantic coast and along the Gulf of Mexico. Precipitation in Mexico was profuse.