Air Temperature

Cool or occasionally even cold weather that settled in Central Russia at the end of spring gradually migrated to the beginning of summer. June started with a frosty night in the Tver and Yaroslavl Regions (air temperatures in the range of -2…-4°), and with weak frosts in the Moscow and Kaluga Regions. The average air temperature in the first decade of June was 1-2° below its normal value in the Central Black Earth regions. However, everything changed later on: from the second decade to the end of the month, abnormally hot weather was observed everywhere in the ETR. New temperature maxima were gained again and again in the area from the Russian North to the North Caucasus. Sometimes, they were recorded for several days in succession, and some of them, e.g., in Saint-Petersburg, were new absolute values ever observed in June. The thermometer readings rose above +35° and closely approached the forty-degree mark. The anomalies of heat in this territory reached 2-5° in the second decade, and 5-9° or more in the third one. As a result, the monthly-averaged temperature exceeded the normal value by 2-4 or more degrees, and this June in the ETR was ranked the hottest one in the history of meteorological observations. The rank was the same in the North-West Federal District and in the city of Saint-Petersburg in particular. This June in the Central Federal District was the hottest in the 21st century and the third hottest in history.
Another region to attain extremely high temperatures during the month was the Far East, most notably, Yakutia where the air temperature rose above 30-35° sometimes. New daily maxima were repeatedly recorded both in the south of the Far East (in the Amur and Sakhalin Regions and in the Primorye Territory) and in its north (in the Republic of Yakutia, in the Magadan Region and on the Arctic coast), with the anomalies of monthly-averaged temperatures reaching 2-5° or more. In the north, this June was the third warmest in the history of meteorological observations. Moreover, the last three years (2019-2021) occupy all the top three lines in the ranked list of monthly-averaged temperatures.
Between these two centres of hot weather, a cold bag covering most of Siberia and the Urals was formed. There, frosts down to -2…-4° took place in the Krasnoyarsk Territory, in the south of West Siberia (Omsk, Tomsk and Novosibirsk Regions) as well as in the Irkutsk and Sverdlovsk Regions, and the monthly-averaged temperature turned out to be 0.5-1.5° below the normal value. Yet, no record low temperatures were observed in these areas.
The meteorological chronicle of Russia will mark June 2021 as the second warmest in the history of regular meteorological observations, i.e. since 1891. 2012 was the only year when the average temperature in June was even higher.
The counties of East Asia (China, Japan, Korea and Mongolia) were in the zone of excessive heat in June. The normal monthly-averaged air temperatures were exceeded by 2-4° or more in some locations of China and Mongolia, by 2-3° or more in Japan and by about 1° or more in Korea. In China, the second highest average temperature previously achieved in June 2011 was reproduced, June 2005 preserving its leading position.
In most countries of South-East Asia, June was also warmer than usual, by 1.0-1.5° or so. Negative anomalies of monthly-averaged temperatures were only recorded in some locations of Philippines.
The weather in the Hindustan Peninsula remained cool for the second month in a row. The monthly-averaged temperature in India and Pakistan was 1-3 or more degrees lower than normal. In India, this June was among the fifteen coldest in the history of meteorological observations, i.e., since 1891.
Heat reigned in the Near and Middle East. The air temperature in Oman, Iraq, Kuwait and the UAE reached +50° and more sometimes. In Yerevan, the capital of Armenia, new daily temperature maxima were recorded for nine days in succession; one of those maxima, measuring as high as +41.1°, was a new highest value ever seen in June. The air temperatures were 2-4 or more degrees higher than normal all over the region except for the Mediterranean coast.
In North Africa, the monthly-averaged air temperature was above-normal everywhere, especially in the north of the continent in Algeria and Tunisia where the anomalies reached +3-5° and above. In the past, the average temperature of June in North Africa was higher than in 2021 only once: it happened two years ago.
The weather in Central Asia was hot. New daily temperature maxima were recorded in Uzbekistan and Turkmenistan. In Kazakhstan, the air heated up to +35-40° or more, but in the third decade, colds not observed for almost 70 years came to the east of the republic. The air temperature during night hours dropped to +4-8°. Yet, the month turned out to be much warmer than usual in most of the region, with the anomalies of monthly-averaged temperatures reaching +2-4° and more. The north-east of Kazakhstan, i.e., part of the country adjacent to then-cold West Siberia, was the only territory where the average temperature in June was lower than normal, by about 1° or more.
In all European countries, the average temperature in June was higher than normal: by 2-3 or more degrees in many territories. This month was the second warmest in the history of meteorological observations in the continent. Only the first summer month of 2019 was even warmer. The thermometer readings sometimes rose to +40° in Sicily and Cyprus, to +36-37° in the south of Spain, to +30-34° in France, and to +35-39° in Croatia. New record-breaking temperatures were observed in Montenegro, Slovenia, Bosnia, Serbia, Croatia, Poland, Lithuania and the Czech Republic. In some countries, they were higher than the previous maxima observed in June: this includes Belarus where the new record-breaking value of +35.8° for July duplicated the absolute maximum for summer achieved on August 8, 2015.
In the last decade of June, heat seized the western territories of the US and Canada. The air temperature in the Canadian province of British Columbia reached +49.6° creating a new temperature maximum in the country after several days of daily temperature highs following one another. Temperatures above 45° have never been measured in Canada before. At the same time, new temperature maxima were recorded in the US states of Oregon, Washington and Idaho, as well as in northern California. For the first time in history, the temperature crossed the 40° mark in Seattle, the capital of the state of Washington, and reached +54° in the Death Valley. Such temperature extremes claimed the lives of 130 people, and caused a lot of fires in Arizona. In most of the United States and Canada, this June was 2-4 or more degrees hotter than usual. In overall, it was the warmest June in the history of meteorological observations in the US beating the pervious 2016 record-breaking value, and the third warmest in Canada alongside June 2012. In the latter case, June 1995 remained invincible still.
In June 2021, the average temperature in the Northern Hemisphere reproduced its all-time maximum recorded in 2016 and later regained in 2019 and 2020, to 0.1° accuracy.
This June, the average air temperature in Moscow was 20.5°, corresponding to a +3.9° anomaly. This is the third maximum value in the ranking list since 1891. June 1999 and June 1956 were the only ones warmer than that. New maxima of daily temperatures were recorded, and June 23 was the day when the temperature reached a new maximum of +34.8° for June.
Ocean Surface Temperature
La Niña dwelling in the Pacific Ocean for ten months from August 2020 until May 2021 came to its end giving a way to weak positive SST anomalies (less than 0.5°) characteristic of the neutral phase of the Southern Oscillation. In the Northern Hemisphere, the average SST anomaly in the Pacific Ocean was the same as in the previous month, but less than in June 2020. A belt of large positive anomalies (higher than 1-2°) arose at the subtropical latitudes of the Ocean. Overly cold water was observed at the eastern tropical latitudes and in the Sea of Okhotsk.
As regards the Atlantic Ocean, high positive anomalies (exceeding 1°) were also observed in the subtropics as well as along the coast of Canada, in the North or Baltic Seas, and in the western Mediterranean. The temperate latitudes between America and Europe hosted abnormally cold water. The average SST anomaly weakened compared both to May of this year and to June of the previous one.
Even though the monthly precipitation totals in most of the ETR save for its southern regions were either normal or sub-normal, occasional heavy rains were unavoidable. In particular, they took place in the north-western regions at the end of the second and third decades. The rain intensity in the Pskov, Leningrad and Archangelsk Regions, in the Republic of Karelia and in the Nenets Autonomous District reached 20-30 mm per day, and a single torrential rain in Saint-Petersburg brought almost quarter of the normal monthly precipitation amount. But the downpours were heaviest in the Crimea and North Caucasus, as well as in the Rostov and Vologda Regions. In the middle of the month, up to three times the normal monthly precipitation total fell overnight in the eastern Crimea and 80% in Simferopol. At the end of June, rains hit the Crimea again and took hold of the Krasnodar Territory were their first wave at the beginning of the month was still in memory. In Sochi, the normal monthly amount of rainwater was collected just for a single night. Yalta, Gelendzhik, Anapa and Sochi were most affected by heavy showers: the streets in these cities turned into rivers. In June, two to four times the normal precipitation amount fell in the Crimea, and more than 1.5-2.0 times, in the Volgograd, Rostov and Saratov Regions, in the Krasnodar Territory and in the republics of the North Caucasus.
The monthly precipitation quantities were less than normal in the Urals, and normal or greater than that in Siberia. Up to 1.5 times the normal amount fell in the south of West Siberia (in the Novosibirsk Region and the Altai Territory) and of the Krasnodar Territory, as well as in Taimyr. In some places, the total precipitation figures were updated by up to 30 mm of rain each day. Snowfalls were still observed in the Khanty-Mansi Autonomous District.
In the Far East, the precipitation everywhere apart from Chukotka was abundant, especially in Yakutia and in the southern regions of this Federal District (the Trans-Baikal and Primorye Territories, the Republic of Buryatia, the south of the Khabarovsk Territory, the Amur and Sakhalin Regions). In certain locations, from 20 to 60 mm of rainwater were collected per day, and the normal monthly amounts were exceeded by 1.5-2.0 times.
In Japan, the monsoon was slowly moving from the south to the north. In some places, the daily precipitation reached 100 mm, and the authorities were forced to evacuate people due to heavy rains and landslides. Yet, the monsoon was still weak, and the resulting overall monthly distribution in June was characterized by less precipitation than normal. The total figures in China were low as well, with the exception of the north-east of the country and some areas of Qinghai, Gansu, Shaanxi, Yunnan and Guangzhou provinces where the normal amounts were reached, or exceeded by 1.5-2.0 times in places. The tropical storm Koguma brought many rains to the island of Hainan.
The mentioned Koguma left its traces in Vietnam and Laos, bringing up to 300 mm of rain and causing floods in some regions. The monthly precipitation totals were about normal in these countries, and less than that in Thailand.
Monsoon showers flooded India, Pakistan and other countries of South Asia. In India, tens of thousands of people were affected in the states of Bihar, Uttar Pradesh and Uttarakhand. The rain intensity reached 20-30 mm per hour. Rains in Nepal and Sri Lanka caused massive flooding and landslides, resulted in severe damages of the infrastructure, and led to fatalities. With the exception of the northern regions of India and southern regions of Pakistan, the monthly precipitation totals everywhere in these countries were either normal or increased. In the southern and north-eastern states of India, they were 2-3 times the normal value.
Almost no rains were observed in the countries of the Near and Middle East. Heavy downpours took place in Turkey only where they caused floods in the north of the country and its capital, Ankara. The overall monthly precipitation totals were 1.5 or more times higher than normal in a significant part of the country.
Traditionally for summer, the weather in North Africa was dry. Abundant rains fell only in Algeria where the precipitation amounts in the west were 1.5-2.0 times larger than normal, and in the southern countries, namely, in Burkina Faso, Nigeria, Cameroon, Benin, Togo and Ghana where rains caused floods, and the fatalities were reported.
The weather was dry in most of Central Asia. Rains came to the north-eastern regions of Kazakhstan only, where their monthly figures were approximately normal.
June in most of Europe was dry. The monthly precipitation totals reached or exceeded the normal values only in Germany, France and the north of Spain, as well as in Ukraine, Romania, Bulgaria and Greece in the south-east of the continent. On the first day of summer, snow still fell in the Ukrainian Carpathians, and intensive rains (up to 20-30 mm per hour) caused floods in France and Belgium. This month, France suffered more than once from pouring rains. Downpours were observed in Romania, Bulgaria and the south of Ukraine, and hit England and Wales at the end of the month bringing more than 50 mm of daily rainwater in some places there. Switzerland, Poland and Spain were also not left neglected by occasional heavy rains.
The eastern and south-eastern territories of the US were flooded with rains. Many of them were brought by the tropical cyclones Claudenne and Danny from the Atlantic Ocean. In Alabama, Mississippi and Louisiana, 200-250 mm of rain fell per day in places. Georgia and South Carolina received a little less than that. In Michigan, more than 150 mm of rain fell for a single day in the city of Detroit, while in Missouri, rains led to massive flooding. The monthly precipitation totals were normal or increased in this territory and two or more times higher than normal in some locations of Missouri, Indiana, Alabama, Mississippi and South Carolina. At the same time, almost no rains fell in the west of the country in California, Nevada, Arizona, Idaho and Montana. The drought in California was just for a short time relaxed by the tropical storm Enrique which, along with the storm Dolores, was culprit for abundant rains in Mexico were the monthly precipitation totals were normal, or increased – exceeding the normal value by 1.5-2.0 times in some places. In the middle of June, rains hit Panama where they caused mudflows, and at the end of the month, heavy showers flooded Caracas, the capital of Venezuela. In the west of Canada and partially in its central provinces of Manitoba and Ontario, the weather was as dry as in the USA, whereas in the rest of the country, the precipitation amounts were normal or somewhat increased.
In Moscow, 62 mm of rainwater fell in June: this is 83% of the normal quantity.