MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHEN HEMISPHERE AS OF MAY 2022

Air Temperature

The whole month in the ETR was abnormally cold. In each of the three decades, there were areas of decade-averaged temperatures 2-4° lower than normal, and in the first decade, five or more degrees lower. New daily temperature minima were recorded everywhere from the Volgograd Region to the Lower Volga, and the resulting monthly averages turned out to be 2-3 or more degrees below the normal values in the Central, Volga and Southern Federal Districts. The last time such a cold May was logged by the statisticians some twenty years ago in 1999-2002, though in the Volga region, May 2017 was also very cold. But in the last days of the month, the record-breaking heat came to the north and south of the ETR, and new temperature maxima were measured in the Arkhangelsk Region as well as in the Krasnodar and Stavropol Territories.
In contrast to the ETR, the weather in the Urals and in Siberia was mostly warm or even hot from time to time. In the history of meteorological observations, this May was the second warmest in Siberia, yielding to May 2020 only, and the fourth warmest in the Urals where the monthly-averaged air temperatures were 4-8° higher than normal, and the decade-averaged ones, 6-12° higher in the second and third decades. Numerous daily temperature maxima were set all the way from Taimyr to Altai, Khakassia and the south of the Krasnoyarsk Territory.
In the Far East, above-normal temperatures were recorded in the north of the region only (in Chukotka, Kolyma and northern Yakutia), accompanied with new temperature maxima. Meanwhile, the temperature background in the south was normal. As a result, the monthly-averaged air temperature turned out to be 2-4° higher than normal in the north, and close to normal in the south, even at a negative background in some places.
In the Asian Territory of Russia, this May was the second warmest in the meteorological chronicle of the country, with May 2020 at the leading position. As for the whole Russia, the average temperature in May was ranked the fifth highest.
May concluded the calendar spring: this year, the average spring temperature was close to normal in the ETR, and 2-4 or occasionally six degrees higher in the ATR, so that this average for the whole Russia was outside the Top Ten highest recorded for the entire period of regular meteorological observations since 1891.
The monthly-averaged temperature was normal in most of China, slightly higher than normal in the north and north-east of the country, and slightly lower in the south. In Xinjiang, the anomalies exceeded 4-5° in places. The averages in the Korean Peninsula and in Japan were normal or a bit increased. At the end of the month, the thermometer readings on the Japanese island of Honshu rose above 28° to produce new daily maxima in some of its places.
The air temperature in South-East Asia was close to normal. The same can be said about India, but in the north of the country, the air in some locations heated up to 45-49°, and the anomalies of monthly-averaged temperatures reached or exceeded 2°, roughly as was the case in Pakistan.
The temperatures in the Near and Middle East were either normal or above-normal. The latter primarily concerns Iran and certain areas of Saudi Arabia where the anomalies reached or exceeded 2-3° in some places.
In North Africa, the normal values were noticeably exceeded in Tunisia, Algeria and Morocco only, by 2-3 or more degrees.
In Central Asia, the weather in the western territories and in the eastern ones was strikingly different. In the west of Kazakhstan, it was colder than usual, to end up in negative monthly-averaged anomalies of -2…-4° in the West-Kazakhstan and Atyrau regions; negative anomalies were also recorded in Turkmenistan and in the north of Uzbekistan. But the eastern Kazakhstan and the rest of Middle Asia received more heat than usual, and the air in these areas heated up to extra 2-3 or more degrees in some regions.
In Western Europe, hot weather came in the middle of the month with the air temperatures above 30° in France and above 40° in Spain. New daily temperature maxima were established here and there, and the normal temperature averages were exceeded by 2-4° or more everywhere from Poland and Hungary to Spain and England. At the same time, cold weather prevailed in the east of the continent. In the Baltic countries, in Belarus and in the east of Ukraine, the month was colder than usual, with frosts down to -4° still taking place in Belarus in early May and resulting in new temperature minima. Yet, owing to the contribution of the hot part of the continent, this May was ranked the third warmest after May 2018 and May 2003 in the meteorological history of Europe.
Similar to Europe, North America was divided into hot and cold areas, with the hot areas now prevailing in the east of the continent, and the cold ones, in the west. Hot weather dominated in the regions from the Atlantic Ocean to about 100°W as well as in the south of the US, with the monthly-averaged temperatures 2° higher than normal, or 4° higher in some locations of Texas and New Mexico in the south. Westwards as far as the Pacific, the month was cold but not overly so. The weather in northern Canada and in Alaska was warmer than usual, by 2-6° in places. The temperatures in the north of Mexico were noticeably higher than normal.
In the Arctic, May 2022 entered the Top Ten warmest in history due to large positive anomalies in Canada and Russia.
Regarding the Northern Hemisphere of the Earth in overall, the average temperature was ranked the fourth to seventh highest for May and third to fourth highest for spring in the entire history of meteorological observations. This spring was the warmest in China where the record dated four years ago was beaten, and the second warmest in India where the record dated 2010 remained unbeaten still. This spring was 2-4° warmer than usual in the Asian continent, or up to 6° warmer in the north-east. The temperatures were 2° above normal in the Arctic, in Mexico, in the south-west of the US and partly in the western countries of Europe. The trends of temperature anomalies in Eastern Europe, in the west of the US and Canada as well as in the tropical and equatorial water bodies of the Atlantic and Pacific Oceans were generally negative.
In Moscow, May 2022 was cold. Its average temperature was +10.7°: this is a -2.4° anomaly. A similar average was recorded in May 2017. Negative anomalies in May have been observed eight times for 22 years in the 21st century.

Sea Surface Temperature

La Niña, a cold episode of the Southern Oscillation, was still in place this May in the Pacific Ocean. Negative SST anomalies in the equatorial belt were observed in water bodies from the coasts of South and Central America to a 160°E longitude. The areas of abnormally cold water spread as far the US coast to the north of the equator in the Northern Hemisphere and as far as the coast of Chile to the south of the equator in the Southern Hemisphere.
In the Northern Hemisphere, high positive SST anomalies (exceeding +1...+3°) were recorded in the subtropical and temperate latitudes of the Pacific Ocean, whereas the anomalously cold water on the oceanic surface, in the South China Sea, along the coast of the Sea of Okhotsk, and in the north of the Bering Strait.
As for the Atlantic Ocean, the average SST anomaly in May dramatically increased to a value greater than a year ago. The SST was above-normal almost throughout the entire water area and in the marginal seas of the Ocean. Negative anomalies were only recorded in the north at the junction with cold Arctic waters.

Precipitation

The precipitation totals in May were normal or above-normal in most of the ETR save for some regions of the North Caucasus where the normal values have not been reached. Above-normal figures 1.5-2.0 times the normal ones were recorded in the Vologda, Kostroma, Kaluga, Kursk, Samara, Penza and Ulyanovsk Regions, as well as in the Republics of Mordovia, Tatarstan and Bashkortostan where heavy rains sometimes brought 30 or more millimetres of atmospheric moisture per day. Snow was still falling in the north of the ETR.
In the Urals, precipitation was normal or increased, amounting to 1.5-2.0 times the normal quantities in the south (in Sverdlovsk and Chelyabinsk Regions). Siberia, with the exception of Taimyr, Evenkiya and the southern regions of the Krasnoyarsk Territory, received insufficient atmospheric moisture in amounts less than 50% of the normal value. A lot of precipitation was observed in the north, resulting in the record-breaking daily totals in some locations. Precipitation was scarce around Lake Baikal and in Chukotka, but normal or higher than normal in the rest of the Far East, e.g., 1.5-2.0 times higher in the Amur Region, Sakhalin and Kolyma. Extremely heavy rains bringing up to 50 mm of rainwater in a single day pelted from time to time in Kamchatka, Sakhalin and the Kuril Islands to set up new maxima of daily precipitation totals. Snow was still observed sometimes in these areas.
In the south of China and on the Japanese islands, the summer monsoon set in at the end of the month. As a result, the monthly precipitation totals either reached or exceeded the normal amounts. Up to 39 mm of rainwater accumulated per day in the north of Japan (on Hokkaido Island) and up to 100-120 mm, in the south of the country (on Kyushu Island). The weather in most of China was dry; there, the monthly precipitation totals not even reached 50% of the normal amount.
Precipitation was mostly normal in South East Asia where the rainy season has also begun. Heavy showers caused massive flooding in Indonesia where the height of floods reached one and a half of metres in some places.
India was invaded by rains. In the south and east of the country, the monthly rainfall totals were two or more times greater than normal, and the downpours resulted in floods. A similar picture was observed in neighbouring Bangladesh and Sri Lanka, as well as on the Andaman and Nicobar Islands. Yet in the north-west of India and in its adjacent Pakistan, the weather was still dry.
Likewise, the weather was dry everywhere in the Near and Middle East, as well as in most of North Africa. In the countries of the Horn of Africa, severe draughts were observed. Only in the south west, heavy rains hit Senegal, Guinea and Sierra Leone where the precipitation totals were normal or 1.5-2.0 times greater than that.
Dry weather prevailed in most of Kazakhstan and of the Central Asian republics, with the exception of the southern Kazakhstan and certain regions of Uzbekistan and Turkmenistan where the rainfall amounts reached the normal values or exceeded them in some places.
Precipitation in the western, central and southern parts of Europe was scarce, amounting to less than 50% of the normal values as a rule. Météo France reported that no such draught had been seen in the country for a long time. Scanty amounts of precipitation have been observed in France from the previous autumn to the end of this spring. In May, rains in Europe fell in the Baltic countries and Belarus in the east, and in the Scandinavian countries and the UK, at a normal rate.
The amounts of atmospheric moisture in the USA excluding the south-western states and in Canada excluding its northern territories were normal or greater than normal, 1.5-2.5 times greater in some locations. Almost no rains were observed in the south-east of the United States from California to Texas.
In Moscow, 67 mm of rainwater accumulated in May: this is 131% of the normal amount. Unprecedented rain in the capital occurred at night on May 27 bringing as much as 26 mm of precipitation in 12 hours and setting up a new daily maximum.