Air temperature

Arctic colds hit the ETR in the first days of May and dominated there for most of the month, although their strength was especially noticeable in the first decade. No such prolonged colds had ever been observed in Central Russia at this time of year. The frosts reached -5…-9° in Central Russia and in the Black Earth and Volga regions, or -4° in the south, and came to the Kaliningrad Region in the west of the country as well. The decade-averaged temperature anomalies reached -4…-7 or lower degrees. In the second decade, the colds persisted (within the decade-averaged temperature anomalies down to -4° or colder), but started to give up already, up to the normal or even above-normal
values in the north-east of the country. At the beginning of the third decade, the abnormal colds in the east and north-east of the ETR still survived, but the weather in the north-west became extremely warm: new temperature maxima were recorded in Karelia as well as in the Vologda and Arkhangelsk Regions, and the thermometer readings would rise to such values that could be measured in July, and not every year for that matter. Yet, much more temperature minima were newly set in the ETR this May, especially, in the first and second decades of the monthFor most days of the month, the weather was colder than usual in the Urals, but predominantly warm rather than cold in the south of Siberia where the colds still reached in thethird decade, with the frosts down to -5° in Altai as well as in the Novosibirsk, Kemerovo, Omsk and Tomsk Regions.

In the Far East, northern territories located in Yakutia and Kolyma where most remarkable: there, the average anomalies of air temperature exceeded +4…8 or more degrees in the first and third decades, and new temperature maxima were set in Yakutia to exceed +30° in some locations.

The cold in the European territory and the warmth in the Asian territory summed up to result in the normal monthly-averaged air temperature of May in the Russian Federation.

As to the average temperature of spring, its value in Russia was slightly higher than normal considering the whole country, but notably lower in the north-east of the ETR and in the Urals, and notably higher in the north of the Far East. This spring was the warmest in the Southern Federal District and the second warmest in the North-Caucasian one. Despite the cold May in Central Russia, the spring in this region was last in the list of top five warmest in the history of meteorological observations, the warmest one still dating back to distant 1921.

In China, this month was the warmest May in the history of meteorological observations: the monthly-averaged air temperatures in most of the country were 2-4 or more degrees higher than normal; almost the same anomalies were observed in the countries of South-East Asia.

In India, the local meteorologists reported that this May was the hottest in the last 36 years. In the north of the country, the air heated up to 47-48°, and the average temperatures were 2-3 or more degrees higher than normal, whereas in the south-east, the weather was relatively cool.

In the Near and Middle East, the average temperature in May was either close to normal, or somewhat higher than that.

May 2024 in North Africa was the hottest in the history of meteorological observations, with the monthly-averaged air temperatures 2-4 or more degrees higher than normal over a large area. In Egypt, the record-breaking air temperatures were recorded, and the thermometers showed up to 42-47° at times.

The weather was hot in Europe; in the north of the continent, the monthly-averaged temperature anomalies exceeded +2…4°, new daily temperature maxima were set multiple times in Sweden and Finland, and the thermometer readings would rise close to +30°. This May was the second warmest in the history of meteorological observations on the continent, yielding to May 2018 only, was the warmest in the UK and the second warmest in Germany.

In the North American continent, the month was very hot: the monthly-averaged air temperatures were 2-4 or more degrees above normal in the north and east of Canada, in the east of the US, and almost everywhere in Mexico. It was the third warmest May in the history of Canada. Unprecedented high temperatures were measured in Mexico, close to 50° in the north of the country. In the Caribbean, this May became the warmest in history.

Regarding the entire Northern Hemisphere, May 2024 turned out to be the warmest in the meteorological chronicle of the planet, and the same was true for the whole spring. The average spring temperatures were 2-4 or more degrees higher than normal in North America and North Africa, in large parts of Europe and China as well as in some regions of India and Indochina, and two or more degrees higher in the east of Russia. The spring was colder then usual at the sub-tropical and northern latitudes of the Pacific Ocean, in the eastern part of the Arctic and, as noted above, in the north-east of the ETR and in the Urals. This spring was marked as the warmest in North Africa, Western Europe, China and Caribbean, as well as in Germany and Austria, and the third warmest in Japan.

In Moscow, May 2024 was colder than normal; its average temperature was +12.7° with an anomaly of -0.9°. The entire spring was warm: due to the average temperature 1.8° higher than normal, it became the fifth warmest spring in the meteorological annals of the capital.

 
Sea Surface Temperature

The major news about the World Ocean was termination of El Niño in May, as confirmed by the appearance of negative anomalies in the equatorial zone in the east of the Pacific Ocean. Off the coast of South America, their absolute value exceeded 0.8°. This has not yet in any way affected the average SST anomaly of the Pacific Ocean in the Northern Hemisphere: the latter anomaly reached the absolute maximum for the eighth month in succession. The highest positive SST anomalies (up to 2-3° or more) were formed at sub-tropical latitudes, while the negative SST ones were small by both their magnitude and area, and were located in the northern part of the Ocean and, partially, at tropical latitudes.

The SST of the Atlantic Ocean in the Northern Hemisphere reached its absolute maximum again, for the 17^th month in a row already. High positive anomalies occupied a significant part of the Ocean, basically at equatorial and tropical latitudes, and partly at temperate ones. The SST of the marginal seas in Europe was above-normal. Negative SST anomalies occupied the northern latitudes along the border with the Arctic Ocean, as well as off the coast of North America south of Newfoundland.

The weather in the ETR was mostly dry this May: normal precipitation amounts were only achieved in the Nenets Autonomous District as part of the North-Western Federal District, in the Yaroslavl, Kostroma and Ryazan Regions as part of the Central Federal District, in the Upper Volga regions and republics as part of the Volga Federal District, as well as in the Krasnodar Territory and the Republic of Adygeya as part of the Southern Federal District. Normal precipitation over the entire territory was observed in the North-Caucasian Federal District only. The Luhansk and Donetsk People's Republics received only about a third of the normal precipitation amounts. In the Russian North, snow remained as late as at the end of May, with the snowdrifts growing during the entire month. At the end of the first decade, heavy rains fell in the Upper Volga and Southern Urals.

In the Urals, precipitation was normal in most constituent entities of the Federation, and above-normal in the south.

In Siberia, precipitation was normal or increased everywhere except for the Republic of Tyva and the Irkutsk Region; in particular, the precipitation totals in the Altai Territory as well as in the Novosibirsk and Kemerovo Regions were 1.5-2.0 times larger than normal, the daily precipitation amounts reached 25-30 mm in certain places, and some regions were snowed in again.

In the Far East, precipitation was abundant solely in Kamchatka where the normal amounts were twice exceeded, as well as on Sakhalin and in the Primorye.

Mongolia, the north-east of China and the western provinces of the latter country received much more precipitation than normal. Precipitation on the Korean Peninsula and in Japan was normal, while in the south of China, in the countries of South-East Asia and in India, the summer monsoon started with heavy rains, and the monthly precipitation totals could be considered significant or even exceptional, as they were 2-3 or more times larger than the normal figure.

Powerful downpours hit Central Asia and the Middle East, leading to numerous floods and mudslides in the north of Afghanistan and resulting in the monthly precipitation totals 1.5-3.0 times the normal values. At the same time, the weather in most of the Near East was dry. In the east of Turkey and in Armenia, heavy rains caused massive floods.

Rains in North Africa were observed in the west of the continent and partly along the Mediterranean coast where the monthly rainwater totals were 1.5-2.0 or more times greater than normal in places. Heavy rains in Kenya were reported to result in severe flooding.

In mid-May, downpours leading to floods hit Central Europe and Northern Italy; there, the normal precipitation amounts were exceeded by 1.5-2.0 times in some places. This May was the wettest in the meteorological history of Switzerland and the third wettest, of Germany.

In Canada, the normal amounts of atmospheric moisture were noticeably exceeded in the province of Yukon in the north-west of the country and in the provinces of Saskatchewan and Manitoba in the central part, while the weather in the north and south-west was dry. In the USA, a lot of rain fell in the eastern and south-eastern states, whereas the centre and south-west of the country were in dry weather conditions, as was Mexico – now a victim of an unprecedented drought.

In Moscow, 37 mm of precipitation fell in May, i.e., 72% of the normal amount, and 151 mm accumulated in spring, which is normal. Over the first five months of the year, the capital received a third of the normal annual figure.