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

Air Temperature

After a hot weather anomaly in July, a gradual cooling came to the ETR with the beginning of August. In the first decade, it happened in the Central and partially the Southern Federal Districts, whereas in the north, the Volga region and the Caucasus, a moderate heat persisted still: there, the decade-averaged temperature anomalies reached +2…4° or more degrees. New temperature maxima were recorded on the Kola Peninsula, in Novaya Zemlya and in the North Caucasus, but soon, the weather there became cold as well.

In the second decade, heat was lacking almost in the entire ETR. The decade-averaged temperature anomalies in Central Russia reached -2.0…-2.5°. The weather was warmer than usual in the extreme north of the ETR only, but the colds reached even there in the third decade. Anomalies in Karelia and in the Leningrad Region amounted to -2°; sometimes, the thermometer readings dropped below zero, and new daily temperature minima were recorded. Temperatures in Central Russia and in the Volga region were subnormal still, and approached there normal values in the south only.

In the northern Urals and Siberia, the weather was abnormally hot all over the month, with the normal temperature values exceeded by 3-5° or more in each decade, and new air temperature maxima recorded repeatedly. In Norilsk and Dickson, this August was the warmest in the history of observations, and in the Arctic islands of the Kara Sea, multiple temperature maxima were measured. There, the temperature exceeded +25°. In the south of Siberia, the weather in the first decade was noticeably colder than usual, ending up with frosts and new temperature minima in some places.

In the Far East, the temperature patterns were close to normal for most of the month; on occasional days, frosts down to -4° occurred in the north of the region. The weather in southern Sakhalin and on the Kuril Islands was abnormally warm.

As a result, the monthly-averaged air temperature was close to normal in most of Russia, but much higher than that in the north-east of the ETR, in the north of the Urals and of Siberia, as well as in the Arctic (with anomalies of +2…+6°). On the monthly average, the weather was warmer than usual in the south of Sakhalin and on the Kuril Islands. Due to this, and because air temperature anomalies were universally positive, August 2025 was the third warmest in the meteorological history of Russia (alongside 2007 and 2016), with August 2023 still the leader.

August marked the end of the calendar summer. In the Asian Territory of Russia, this summer was the second warmest in the history of meteorological observations (albeit that together with three other years: 2016, 2021 and 2024), but in the ETR, it was only among the second ten warmest, preventing it from entering the first five in history on the country scale and putting it on the 6th to 8th position in that ranking list.

The weather in East Asia was hot. Temperatures in Shanghai exceeded +35° for most of the month, and their monthly averages in eastern China, Korea and Japan were two or more degrees higher than normal. In China, this August was the third hottest in history. In Japan, the all-Nation high of the air temperature was surpassed again, and this August became the second warmest on record.

Temperatures in the countries of South-East and South Asia were about normal.

The weather in the Near and Middle East was extremely hot: in early August, very high temperatures in excess of +50° settled in the Near East everywhere, close to the record-breaking values in many locations. New temperature maxima were recorded in Turkey, and the climatic norms were overridden by two or more degrees in Iran and in the South Caucasus countries.

In Central Asia, the weather was much hotter than usual. The monthly-averaged temperature anomalies in the Central Asian republics and in the south of Kazakhstan were higher than +2-3°.

Temperatures in North Africa were approximately normal.

Even though the average air temperature was close to normal in most of Europe, it was notably greater in some areas such as the south-west or south-east of the continent. In the first half of the month, a scorching hot air from Africa would reach the Iberian Peninsula, and the temperatures could grow up to 42-45° in Spain or up to 40-42° in southern France where the monthly-averaged temperature anomalies were +2° or higher. The monthly-averaged air temperature in Spain reproduced the all-time achievement of 2024, while in Cyprus, Greece and Albania in the south-east of Europe, the weather was also very hot, and new air temperature maxima were recorded in some places.

In most of the North American continent, the temperatures also kept close to normal: at the background of weakly-negative anomalies in the east of Canada and of the US, and of weakly-positive ones in the rest of the territory. Only partially in the north-west of Canada, the south-west of the USA (in South California and Arizona) and the north of Mexico, the air heated to 2° above the normal value on the monthly average. As reported by the US Weather Service, this August in Arizona was the second warmest in history. In southern Florida, new temperature highs for August as well as new monthly averages for any calendar month were recorded.

This August was ever warmest in the Arctic, with its average temperature the same as in August 2023; first of all, this was contributed by the abnormally warm weather in Greenland as well as in the Barents, Kara and Laptev Seas, where the monthly-averaged temperature anomalies on the islands and along the coast were +2…6° or more.

The average temperature in the Northern Hemisphere was ranked the third warmest in the meteorological history, August 2024 and August 2023 being the only ones even warmer.

The summer as a whole had the same rank: it was warmer than normal in all the parts of the Northern Hemisphere (except for the Hindustan Peninsula, the north-east of Russia, the north of Greenland and the north-east of Canada). The climatic normal values of summer were exceeded by 2-4° in eastern China, Korea and Japan, by 2-3°, in the north of the Urals and of Siberia, by 2° or more, in the south-west of Europe, and partially in western China and in the eastern regions of ex-Soviet Central Asia. Also, this summer was unprecedented warm in the UK and in Ireland, the third warmest in France, and the third warmest in the meteorological chronicle of the European continent.

In Moscow, the average temperature in August was +17.1°, with an anomaly of -0.5°. A subnormal temperature in August was last measured in 2019. The summer temperature average was close to normal.

Sea Surface Temperature

In the Northern Hemisphere, the monthly-averaged SST of the Pacific Ocean reached its maximum for the fourth month in a row, this time, reproducing the record-breaking value set in August of the previous year. It should be noted that this happened when the Southern Oscillation was in the neutral phase rather than during El Niño when the Ocean was warming. At the equatorial latitudes, weakly-negative SST anomalies were detected, while at the subtropical and temperate ones, the monthly averages were 2-4 or more degrees above the normal values. Moreover, such anomalies were observed across the entire surface of the Ocean everywhere from Asia to North America. The monthly-averaged SST was above-normal at the northern latitudes as well (in the Bering Sea, the Gulf of Alaska, and the Bering Strait).

The trends in the Atlantic Ocean were different. There, anomalies in most of the Ocean can not be regarded as extreme, but should only be termed this way in the Gulf of Mexico, the Caribbean Sea, and partly off the US coast, or off the coast of Europe including that of the Mediterranean Sea. High positive SST anomalies (+2-4°) were formed in the Greenland, Barents and Kara Seas in the north.

Precipitation

Most of the ETR received abundant precipitation in August: its normal figures were exceeded by 1.5 times in the north and north-east of the Volgograd and Kaliningrad Regions, measured likewise in the Lipetsk, Orel, Tula and Ivanovo Regions in part of the Central region, and exceeded twice in the Kostroma Region as well as in the Kirov Region included in the Volga Federal District. In other subjects of the Federation from this region such as the Nizhniy Novgorod Region, the Republics of Mari El, Chuvashia, Tatarstan, Bashkortostan and Udmurtia, the excess was more than 1.5 times the normal amount. The shortage of precipitation took place in the south of the ETR only, i.e., in the Southern and North-Caucasian Federal Districts where the normal amount was solely reached in Kalmykia, the Krasnodar Territory, Karachay-Cherkessia and the Donbass republics, while the precipitation figures elsewhere were lower: less than a half the normal quantity in Crimea, in the Rostov Region and in Northern Ossetia.

Heavy rains in the first decade passed across Central Russia, the Krasnodar Territory, the Volga region and the north-western areas, bringing up to 20-60 mm of atmospheric moisture per day. In the second decade, showers once again attacked Central Russia, the north-west and the Volga region, and in the third, the south of Kuban, and the above territories again, with the daily intensity of precipitation estimated as 20-40 mm. At the same time, a deficient precipitation in Crimea resulted in drying-up of the rivers.

In the Urals, precipitation was roughly normal; however, heavy rains fell there at the end of the first decade.

Western Siberia, Altai and the south of the Krasnoyarsk Territory were flooded with rains that brought 1.5 times the normal precipitation or more, e.g. 2.0-2.5 times in Altai. The normal amounts were not reached in the northern regions of Siberia only, with less then a quarter of the normal quantity in Taimyr. Heavy downpours were observed in the south of Western Siberia and of the Krasnoyarsk Territory, as well as in the Irkutsk Region (20-60 mm/day).

Precipitation was lacking in Yakutia where it was just slightly over half the normal figure across the vast territory of the Republic. In the rest of the Far Eastern Federal District, precipitation was normal or above that, the main bulk coming to Trans-Baikal, Primorye, Kolyma, Kamchatka and the coast of the Sea of Okhotsk. At times, the precipitation intensity in latter regions was 40-70 mm per day.

The precipitation totals in Russia were normal or above-normal almost everywhere in the ETR except for its southern regions (Stavropol and Krasnodar Territories, the North Caucasus, Crimea and Donbass). The figures in the Urals, in most of Siberia and of the Far East were also normal. Scanty precipitation was observed in Taimyr and Evenkiya, in the north of Yakutia and in Chukotka.

Showers in China caused floods in the eastern and central parts of the country where the normal precipitation amounts were exceeded by two or more times. In the province of Inner Mongolia, the normal monthly quantity fell during one day. Monsoon rains led to floods and landslides in the southern province of Guangdong. In the Korean Peninsula, precipitation was about normal.

Ample rain fell in South-East Asia, with the normal monthly amounts in northern Vietnam exceeded by 2-3 times.

Monsoon downpours inundated India and Pakistan. This year, the monsoon season was especially intense, multi-day torrential rains causing numerous floods in these countries. The precipitation totals in northern India and eastern Pakistan were rated exceptional, i.e., more than three times the normal quantity, with hourly rainwater amounts exceeding 100 mm in places. River levels rose higher than the record-breaking values, resulting in catastrophic floods in the states of Punjab, Jammu, Kashmir and others: no such natural disasters have been seen there for more than forty years. Many houses were destroyed, castle killed, and large part of agricultural crops wiped out. The city of Mumbai (Bombay) was submerged.

The weather in the Near and Middle East as well as in Central Asia was dry. Heavy rains fell in the south-west of the Arabian Peninsula and in the north of Kazakhstan only.

In North Africa, rainfall was plentiful on the Mediterranean coast of Egypt and Libya, in the Sahel region and in Sudan. Downpours in the latter country lasted several days in succession, and caused significant economic damage. In these areas, the normal monthly precipitation was reached or exceeded.

In most of Europe, the weather was dry, and thus, the monthly precipitation totals were notably lower than usual, reaching the normal value solely in the east (in Belarus and in the Baltic states) and the north of the continent (in the Scandinavian countries). The UK Met Office reported that the country was experiencing the worst drought in the past fifty years.

A shortage of precipitation took place in the US and in Canada. The US Weather Service claimed that this August was the driest in the history of observations in the states of Kentucky, Tennessee and Ohio. A catastrophic drought was observed in Nevada. Rain fell only in the Rocky Mountains, in the Pacific Coast states in the west, and in Alabama, Georgia and Florida in the south-east. Heavy rains caused floods in central Mexico, resulting in significant economic damages. A severe drought was observed in Cuba.

In spite of a dry August, the precipitation totals in summer were approximately normal in most of the US, and less than that in the south-west of the country. In Canada, summer precipitation was normal in the south and east, and scarce in the north. The figures were close to normal in Mexico. Summer precipitation was normal or above-normal in West Africa, India and Pakistan, in the countries of South-East Asia and in the east of China. Summer rains brought normal amounts of atmospheric moisture to most European countries; at the same time, they were rare in the south-west of Europe (Spain, Portugal and France) and in its south-east (the Balkan states).

In Moscow, 92 mm of precipitation fell in August, amounting to the normal value. The summer rainwater amount was also normal, 291 mm in total.