Air temperature
Cold weather in the ETR seamlessly migrated from June to the next summer month. In the first decade of July, negative anomalies of the decade-averaged air temperatures were -1…-2° or higher in the north-west, and anomalous heat was recorded in the Upper-Volga and Trans-Volga regions only where it reached +40° during midday hours and begot new daily temperature maxima.
In the second decade, the colds grew even colder and extended to the entire ETR save for the Arctic latitudes, with anomalies reaching -2…-3° or lower values in the central region and with frosts in Karelia and in the west of the Arkhangelsk Region. In the third decade, the colds became somewhat milder, but the decade-averaged air temperature in most of the ETR was still below, or close to, its normal value. In the last days of July, unprecedented high temperatures along with new daily maxima in excess of +30° were recorded in the north-east of the ETR.
The picture was completely different to the east of Volga, viz., in the Cis-Urals and in Siberia: there, the decade-averaged temperatures were 2-6° higher than normal in the first and third decades. New temperature maxima were reported in Bashkiria and in the Southern Urals, with a new annual maximum in Kurgan among them. In the Krasnoyarsk Territory, the weather was abnormally hot at first (with +5° or higher anomalies), but the anomalies became negative (-2…-4°) when cold polar air intruded there in the second decade.
In the Far East, the record-breaking maxima were measured, and new daily ones were set in Yakutia and Chukotka as well as on the coast of the Sea of Okhotsk in the Khabarovsk Territory. Very hot weather settled in the south of the latter Territory, in Primorye and on Sakhalin at the end of the month, resulting in new temperature maxima in a number of locations.
In summary, the anomalies of the monthly-averaged air temperature in July were weakly negative in most of the ETR and in the Arctic region east of the Urals, and positive in the rest of Russia, with especially high values up to +2 or more degrees in the Urals and in the Khabarovsk Territory. This July became the second hottest in the history of Russia (equally hot as in 1998, 2012 and 2016), yielding to even hotter July 2010 only. It was the hottest July in the meteorological chronicle of the Asian Territory, and among the top five warmest ones in the south of the Far East, in Siberia and in the Urals.
In the countries of East Asia, the month was also hot: the monthly-averaged air temperature was higher than normal almost everywhere, two or more degrees higher in the north-west of China and in Japan. In China, the record-breaking heat persisted for a prolonged period, and multiple new temperature maxima were set, including a new annual maximum of +52.2° for the country that was reached in the Xinjiang Uygur Autonomous Region in the north-west. July 2023 was the second hottest (alongside July 2021) in the meteorological history of China; only July 2022 was even hotter. Thus, this month in the country was outstandingly hot for three years in a row. In addition, June 2023 was the hottest in history, so it may reasonably be believed that this summer will be included in, or possibly be at the head of, the list of the hottest ones in the meteorological annals of China. In the north of Japan, the highest temperature in the history of observations was recorded.
The air temperature in the countries of South-East Asia was about normal.
In India, the monthly-averaged air temperature was close to normal against the background of weak negative anomalies. In its neighbouring Pakistan, July was hotter than usual, notably in the north-west where the heat could reach +50°.
The weather in the Near and Middle East was hot, with the air sometimes heated up to +50° in Iran and on the Arabian Peninsula. Abnormal heat persevered in Turkey, the thermometer readings rising up to +45-47° in the south and up to +44° in the west of the country, and the monthly-averaged air temperatures exceeding the normal values by two or more degrees. In Israel and Bahrain, this July was the second hottest in the history of meteorological observations.
Similarly, the heat occupied Central Asia where the anomalies reached or exceeded +2° over a large territory, and the temperatures rose to +40° in the west and south of Kazakhstan, to +45° in Uzbekistan, Tajikistan and Turkmenistan, and to +50° in Afghanistan.
In North Africa, this July was the hottest in history. The monthly-averaged air temperature was higher than normal throughout the entire region, most notably, by 2-4 or more degrees higher in the Mediterranean countries of Morocco, Algeria, Tunisia, Libya and Egypt. In the south of Morocco, a 50° heat was recorded.
In Europe, this July can be called one of the hottest in history: its average temperature was in the top ten highest for 133 years of regular meteorological observations since 1891. The weather was very hot in the south of the continent where the normal values were exceeded by two or more degrees, but the monthly-averaged air temperatures in the rest of the territory were also above-normal everywhere except for the northern countries, the UK and Ireland. At the end of the first decade, the record-breaking heat came to Central and Western Europe to boost the thermometer readings in Luxembourg, Switzerland, France, Austria, Italy, Germany and the Czech Republic as high as +35-37°, and to upgrade numerous temperature maxima. Even in the mountains, the air was heated: its temperature in the Alps reached +25° at a 1500 metre elevation, which was a new record. In fact, the heat persisted until the end of July, spreading further to Slovakia, Slovenia, Bulgaria, Greece and Spain. In Catalonia, the absolute maximum temperature of +45.3° was recorded for the region, and the water temperature near the coast almost reached 29°. In Sicily, the air heated to 48°, i.e., just 0.8° below the absolute maximum for July in Europe. In Greece, this July was the hottest in the last fifty years.
The weather in North America was hot. In Canada, this July was the second warmest in history: its average temperature was only 0.1° lower than in the ever hottest July 2012. The monthly-averaged temperature in the Arctic region was 2-6 or more degrees higher than normal. Elsewhere in Canada, the air temperature was about normal, against the background of negative anomalies in some places.
In most of the US, the monthly-averaged temperature was above-normal, with the exception of the central states where the anomalies were weakly negative. Anomalies of +2° or greater were observed in the north-east and west of the country. The air in Arizona heated up to +48° at times, and the air temperature could remain above +43° for twenty days in succession. The bitumen became so hot that the pranksters fried the eggs on it. The monthly-averaged temperature in July was the hottest ever recorded in Arizona, New-Mexico, Florida and Maine, the second hottest in Louisiana, and the third hottest in Alaska.
This July was very hot in Mexico: its monthly-averaged air temperature was 2-4 or more degrees higher than normal everywhere.
In the Arctic, July 2023 was the third warmest in the history of meteorological observations, chiefly due to the contributions made by the Arctic territories located in Canada, and in the north of the Russian Urals.
Regarding the Northern Hemisphere, this July was the hottest recorded in the meteorological chronicle. The previous record-breaking monthly average reproduced (to an accuracy of 0.1°) in July of the three consecutive years before was finally exceeded this July by more than 0.2°.
In Moscow, the average air temperature was +18.5°, resulting in an anomaly of -1.2°. The last equally cold July in the capital was observed three years ago.
Sea Surface Temperature
At the equatorial latitudes of the Pacific Ocean, El Niño was on a rampage. The SST anomalies off the coast of South America exceeded 3°. This July, the average SST of the Pacific Ocean in the Northern Hemisphere was assigned rank 2 yielding to July 2020 and July 2022 only. The anomalies at the temperate latitudes of the Ocean were positive, and high as well (+1…3 and larger), with the exception of the Japan Sea area where they were negative. Sub-normal SST values were also measured at the tropical latitudes in the east of the Ocean, as well as in the Bering Sea and the Gulf of Alaska in the north.
The Atlantic Ocean in the Northern Hemisphere did not stop to surprise: the absolute maximum of the monthly-averaged SST was recorded there for the seventh consecutive month. The SST anomalies were positive everywhere save for small water areas off the coast of Greenland, and exceeded 2-4° in the north-western part of the Ocean. The SST equal to +37.8° was recorded off the coast of Florida: such high SST has never been measured before. The water in the Mediterranean Sea and other marginal seas of Europe was also very warm. The daily-averaged SST of the Mediterranean Sea was reported to reach 28.7° on July 24, setting a new temperature maximum. The SST anomalies in the Arctic amounted to +5-6° in the Barents and Kara Seas off the coast of Russia. The monthly-averaged SST in the Northern Hemisphere reached the highest mark.
The rains in the ETR were abundant this July. At the end of the first decade, they hit the Moscow, Ryazan, Lipetsk, Voronezh, Tambov and Nizhni Novgorod Regions, the Republic of Mari El and the Krasnodar Territory. Up to 60-100 mm of atmospheric moisture accumulated there per day in some locations. Heavy showers brought the normal monthly precipitation amount in a single day in Nizhni Novgorod, and caused floods in Tuapse.
In the third decade, rains came to the south of Russia again, bringing up to 40-50 mm of rainwater to the Rostov and Astrakhan Regions, the Stavropol Territory, the republics of the North Caucasus, and the Crimea. At the same time, a lot of rains fell in Karelia, in the Volga region and in Moscow, and set new maxima of daily precipitation totals in some places including Moscow. The monthly precipitation totals in the North-West and Central Federal Districts were 2.0-2.5 or more times greater than normal.
Precipitation was mostly normal in the north of the Urals, and sub-normal in the south.
At the beginning of the month, heavy rains fell in the north of Siberia to result in new precipitation maxima in the Khanty-Mansi Autonomous District. In the Irkutsk region, up to 100 mm of rainwater per day were measured in some places, and the water level in the rivers increased abruptly. Torrential rains took place in the middle course of the Ob river, and new maxima of precipitation totals were recorded here and there.
A lot of precipitation went to the Far Eastern Federal District where up to 30 mm of precipitation could fall per day in the Magadan Region. Snow was observed. The record-breaking precipitation was also measured in the Khabarovsk Territory and in the Amur River region. Heavy rains occurred in some areas of Primorye and Kamchatka. As a result, the normal monthly precipitation amounts were exceeded by 1.5-2.0 or more times in the north of the District, but a shortage of precipitation was observed in its south.
In China, the rainy season triggered downpours and landslides in the north and east of the country. During a single day, more than 100 mm of precipitation could fall in the capital of China, or more than 350 mm in one district of this city. No showers of such intensity have been seen in Beijing since the start date of regular meteorological observations, i.e. over the last 140 years. The south-east of the country (the provinces of Fujian, Guangdong and Zhejiang) was hit by a typhoon that brought a huge amount of precipitation, caused floods and destruction, and affected more than 1.5 million people. Heavy rains inundated Mongolia: in a country with typically dry climate, they lasted for several days in a row, caused floods and deluged the capital Ulaanbaatar. In South Korea, rains did not stop for several days in succession, forcing the rivers to overflow their banks, leading to floods, and claiming the lives of people. Heavy downpours also hit the south of Japan; in one of its regions, 110 mm of rainwater fell in an hour, and more than 300 mm, in two days. New maxima of daily precipitation totals were set.
Likewise, the summer monsoon dominated in South-East Asia where the rains in Thailand caused floods that harmed the tourist resort of Phuket.
India and the eastern areas of Pakistan were inundated with rains that induced landslides, floods, and destruction of buildings and roads. The Delhi metropolitan district was among the affected ones. In the north, snow fell in the mountains.
As typical for summer in the Near and Middle East, the weather was mostly dry there, but occasional showers still took place, leading to floods in some locations in Turkey and its neighbouring Georgia. In Kutaisi, 170% of the normal monthly rainwater amount fell in four days, or 75 mm in one day, which was a new record-breaking achievement. In the south-east of Iran, heavy rains led to floods, and the levels of local rivers rose to new unprecedented marks.
The weather in Central Asia was dry, with severe droughts in some areas.
The weather in most of North Africa was also dry. The rainwater amounts were only sufficient in the countries of its western and south-western parts, i.e., in those located along the coast of the Atlantic Ocean and the Gulf of Guinea.
In Europe, precipitation was scarce in the east (in Spain, Italy, Greece and in the Balkan countries), close to normal in the central and western parts of the continent, and above-normal in the north (in the Scandinavian countries, in the UK and in the northern territories of Germany). Fires broke out in Greece due to the heat and to the absence of rains. Individual heavy showers were observed in Romania, Spain and Belarus; in some places, they brought up to 50 mm of atmospheric moisture in a few hours, and up to 20 mm in ten minutes. Rushing water flows in the cities swept away everything on their way.
Precipitation in the countries of North America was scanty: its amounts were normal or increased only in the USA from the Atlantic coast to the central states of the country. Heavy downpours in the states of New York and Vermont caused floods. Rainwater that fell in amounts exceeding 200 mm in some places deluged houses and roads, destroyed bridges, and resulted in fatalities. In the states of Vermont and Connecticut, this July was the second wettest in history, while in the states of Idaho, Arizona and Minnesota, the third driest one.
In Moscow, 160 mm of rainwater fell in July, amounting to 190% of the normal figure and corresponding to the seventh position in the meteorological chronicle of the capital since 1891. The leading position with 186 mm of total rainwater in the capital was awarded to July 1965.
* The air temperature anomalies have been calculated basing on the normal values for 1991-2020, while the anomalies of precipitation totals, on the normal values for 1961-1990 in the Northern Hemisphere and on the normal values for 1991-2020 in Russia, including Moscow.