MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHERN HEMISPHERE AS OF APRIL 2025
The first days of April still brought new records of heat to the ETR. Daily maxima of air temperature were recorded on the Volga, in the Cis-Urals and in the Southern Urals, driving the thermometers to the values close to +25° in a number of places. But by the middle of the first decade, frosts came there again to replace the records of heat with those of cold, and the average air temperature in the first decade turned out to be subnormal in the central and southern regions of the ETR.
At the beginning of the second decade, cold weather with new record-breaking minima of air temperature still persisted in the north-west, e.g., in the Pskov, Leningrad and Arkhangelsk Regions and in the Republic of Karelia, but in mid-April, the unprecedented warmth arrived there with new record-breaking temperature maxima in numerous locations. April in the ETR ended up with yet one arrival of cold weather, and frosts or even record colds spread to the very south – Crimea, the Volgograd, Rostov and Astrakhan Regions, and Kalmykia.
In most of the territory beyond the Urals, the weather in April was warmer than usual; in the north-east, extreme heat persisted for most of the month. In mid-April, record high temperatures above +30° were observed from Omsk to Irkutsk in the south of Siberia: such thermometer readings were only measured there in summer of select years before. The month concluded with record high temperatures in the north of the Krasnoyarsk Territory, in Evenkiya and Yakutia.
As a result, this April was warmer than normal in most of Russia: the monthly-averaged anomalies of air temperature equal to +2…6° were noted in Yakutia, Kolyma, Chukotka and Kamchatka, as well as in the north of the Khabarovsk Territory. This month was also two or more degrees warmer in the Volga Federal District, on the Lower Volga and in the north: in the Kara Sea and in adjacent land areas. April 2025 turned out to be colder than normal in the Russian North, in Crimea and on the Black Sea coast of the Krasnodar Territory. As for the whole Russia, it closed the top five warmest Aprils in the history of observations since 1891. In the north of the Far East, it was the warmest in history, and in the south, among the top three warmest.
In China, this April was the second warmest in the history of regular meteorological observations, yielding only to April 2024. The average air temperature was above normal throughout the country, by 2-3 and more degrees above in the east and north-east. The same anomalies were observed in neighbouring Mongolia, whereas in Japan and Korea, they were about +1°.
The monthly-averaged air temperatures in the countries of South-East Asia were close to normal. In Thailand, the weather was very hot and sultry on some days, the air temperature reaching +40° in the last days of the month.
The thermometers in the central regions of India showed above 40° at times. The monthly-averaged air temperature was about normal in most of the country, but in the north and in neighbouring Pakistan, it was 2-4 or more degrees higher than that. In Pakistan, this April was the second warmest on record.
In the Middle East, the weather was hot, with the monthly-averaged air temperature in Iran 2-4° higher than normal. According to the UAE Meteorological Service, April 2025 was the warmest in the history of observations. In most of the Near East, the air temperature was approximately normal. In the middle of the month, frosts down to -10…-15° were observed in some regions of Turkey: this has not been seen there in the last 30 years, and caused severe damage to orchards.
Extraordinarily high temperatures prevailed in Central Asia for almost the entire month, so that new temperature maxima were recorded in Kazakhstan, Uzbekistan, Turkmenistan, Kyrgyzstan and Tajikistan. The monthly-averaged temperature anomalies throughout the region were +2…5° or more.
In North Africa, the monthly-averaged air temperature in April was close to normal, or about 2° higher than that in some locations. In particular, the latter was the case in Morocco where new daily temperature maxima were set.
Even though the average temperature of April in most of Europe can be considered close to normal, there were areas where it was two or more degrees above that: the south of Scandinavia and the extreme west of the continent. At the end of the month, new daily maxima were recorded in England, Ireland and France. The record-breaking highs were also measured in Belarus, Ukraine and the north of Italy.
The air temperature in the North American countries was close to normal. In the Arctic territory of Canada, the monthly-averaged temperature turned out to be very high: 2-4 or more degrees above normal. The air temperature was also noticeably higher than normal in the south-west of the US, and slightly colder than usual to the south of Hudson Bay in the Canadian provinces of Manitoba and Ontario, as well as in Newfoundland and Alaska.
The average air temperature of the Northern Hemisphere was ranked the second highest in the history of observations, yielding to the last year's value only.
In Moscow, the average April temperature was +8.8° with +1.9° anomaly.
Sea Surface Temperature
The average SST anomaly in the Pacific Ocean did not change from the previous month, with the neutral phase of the Southern Oscillation still in place. Abnormally cold water spread along the equator, and off the coast of Asia in the west. In the rest water area, the SST was close to or above normal. The SST anomalies at the subtropical and temperate latitudes were +1…2°.
The average SST anomaly in the Atlantic Ocean has decreased dramatically: over the most part of the Ocean in the Northern Hemisphere, the SST was normal in April. Negative anomalies concentrated off the coasts of Canada, Greenland and Iceland, while positive ones, off the coasts of Europe and the USA. The water in the marginal seas of Europe including the Arctic was very warm still. The anomalies in the Barents and Kara Seas exceeded +1°.
Precipitation
In April, abundant precipitation in Russia was observed over a huge territory from the Gulf of Finland to the Sea of Okhotsk and Sea of Japan. The normal monthly precipitation was exceeded by 1.5-2.0 times in the European north and by 2.0-2.5 times in the Urals, Siberia and the Far East. Dry weather prevailed in certain constituent entities of the Federation only, in the following federal districts: Kaliningrad Region in the North-Western, Black Earth Region in the Central, Penza Region in the Volga, Astrakhan Region in the Southern, Irkutsk Region in the Siberian, and Chukotka in the Far Eastern Federal District. In the Luhansk and Donetsk People's Republics, the precipitation amounts were significantly less than normal.
Heavy rains and snowfalls would cover particular regions of the country on some days. In the first decade, pelting rain passed across the Krasnodar Territory (bringing up to 25 mm of daily precipitation), and snowfalls hit Central Russia and Crimea with the height of freshly-fallen snow reaching 10 cm.
In mid-April, showers attacked the North Caucasus and brought up to 50 mm of atmospheric moisture per day to some places, setting new maxima of precipitation totals. In the Leningrad and Volgograd Regions, heavy rains (up to 20 mm per day) were observed, while in Yakutia and Khabarovsk Territory, snowfalls would increase the snow cover height by 15-18 cm.
Rains and snowfalls did not stop pestering Russia in the third decade. Record-breaking rains fell in Altai: a new daily precipitation maximum for April was set in Barnaul. Snowfalls in the Perm Territory, in Bashkiria and Udmurtia raised the snow cover height by yet another 10-15 cm. Snow cover settled again in the Leningrad, Volgograd and Tver Regions. The Sverdlovsk Region received an unprecedented amount of precipitation.
The weather in most of China and in Mongolia was dry, leading to the development of dust storms. In China, considerable precipitation was noted in the south and south-east of the country. In South Korea, snow fell in the middle of the month: the last time it happened was almost 80 years ago; there, the height of freshly-fallen snow reached 10-15 cm in some places.
The weather in South-East Asia was rainy. Heavy rain fell in northern Myanmar, and downpours lasting several days caused floods.
Surprisingly, a lot of precipitation went to India: in the north of the country, it caused landslides that resulted in human deaths.
The weather in the Near and Middle East was mostly dry, with the exception of Turkey where rain or even snow fell in certain places.
In Central Asia, almost no rains were observed, except for Turkmenistan in some places.
In North Africa, there was enough precipitation along the coasts of the Mediterranean Sea and the Atlantic Ocean. Elsewhere, the weather was dry.
The monthly precipitation totals in Europe were normal, or less than that. Heavy rains fell in northern Italy in the middle of the month. As much as 100-150 mm of daily rainwater accumulated in the Alpine foothills, causing severe floods. At the end of the month, downpours covered Bulgaria and brought up to 60-70 mm of rainwater to some locations.
The southern and eastern provinces of Canada received a lot of precipitation, in amounts 1.5-3.0 times the normal ones in some places. A similar picture was observed in the east and centre of the USA: at the beginning of the month, heavy showers hit the Midwest (Kentucky and Tennessee) as well as Ohio and northern Texas. In the state of Arizona, such showers have never occurred in April before. The water in local rivers rose above the record-breaking marks, causing floods. In the last decade, rains led to floods in the state of Oklahoma. In the west of the US and in Mexico, the weather was mostly dry.
In Moscow, the monthly precipitation total amounted to 56 mm. This is one and a half times the normal monthly value.