Air Temperature.

During all month the abnormally warm weather dominated in the European territory of Russia (ETR). At the end of the month the warmth was increased. In the first decade the average decade temperature anomalies reached +2…+3°, in the second and third one - +6…+8. The area of the large anomalies gradually enlarged. Record temperature maximums were registered in the Central region and Chernozem area, in the North Caucasus and Crimea, in Volga area and Pre-Urals. Temperature background corresponded to the beginning of spring, not to the winter month. Average monthly air temperatures exceeded the norms by 2-6° and more. In all federal districts, they came to the first ten of the highest values on the record, i.e. since 1891. In the South and Ural districts, it was the warmest December on the record, in the Central one – third, in the North Caucasian – fifth. In the north of ETR in the Kola Peninsula, although it was also warmer than usual, the temperatures were lower than -30°.
In the central and north areas of Siberia the warm weather, as well as in ETR, was kept for all month. The average decade temperature anomalies exceeded +10°. New daily maximums were registered. But the south of Siberia has got a frost in the middle of the month. In Altai republic the frosts reached -35°.

It was even colder in the Far East federal district. In Yakutia the 50° frosts dominated. Surprisingly the weather was changed in the north of Far East. In Chukotka during the first decade it was warmer than usual by 10-12°, in the third one – colder the norm by 2-5°. The cold records have been set in the south of Khabarovsk district and Amur region. Here the frosts reached -40° and lower. Warm west and cold east became the reason of the fact, that in Russia the first winter month of 2017-2018 closed the first five warmest Decembers over 127 years on the record. Leader here remains December 2013.
In any area of the Russian Federation the average air temperature over 2017 became higher the norm. In the most part of European territory – by 1° and more, in the north-east of ETR (republic of Komi, Arkhangelsk region, Nenets Autonomous district), in Siberia and north of Far East – by 2° and more. In the Arctic areas of the West and East Siberia, north-east of Yakutia, Magadan region and Chukchi Autonomous district the average annual air temperature anomalies have set +3…+5°. In the Far East federal district, the last year became the warmest one on the record in the north and the third warmest – in the south. In Russia in general the average annual air temperature reached the maximum in the 127-years weather sequence, having repeated the achievement of 2007 (with accuracy to 0.1°).
During the year in the different regions of the country, the maximum values of the average monthly air temperatures were registered. In general in Russia it happened in March. In the same month, the maximum was reached in Urals, Siberia federal districts and in the north of the Far East federal district. In April, this event was repeated again in the north of the Far East, in December – in the South and Urals federal districts. In no one area of Russia the average monthly air temperatures reached the extremely low values over the year.
Air temperature above the average monthly norm was registered in December in the most part of China. In the north and east provinces the anomalies were +2…3°. Even more they were in Mongolia - +3…5°. At the same time, the east neighbours Korea and Japan have got the cold December. The cold from Russian Far East came here. In Korea even the historical temperature minimums were registered, and in general over the month it was colder than usual by 1-3°.
December air temperature in the south-east of Asia and Hindustan Peninsula approximately corresponded to the norm. In the beginning of the month, it was noticeably colder than usual in the Central Asia. In Kazakhstan, the frost reached -30°. Then the weather was balanced and by the end of December in the east of Kazakhstan and in Uzbekistan the temperature maximums were registered. But the cold overpowered the warmth and average monthly air temperature became below the norm by 1-3°.
It was colder than usual in the south of Arabian Peninsula, at the same time in some countries of the Middle East the temperature exceeded the norm: in Israel, Jordan, Iran, the north of Saudi Arabia – approximately by 2°.
It was cold in the north-west of Africa. In Morocco, Mauritania, Algeria, Tunisia the average monthly air temperature was below the norm by 1-3°. But the average monthly air temperature in the north-east of Egypt were above the norm by the same value. Other North Africa territory has normal temperatures.
Most part of Europe in December were in the abnormally warm weather conditions. From Germany and further to the east everywhere the average monthly air temperature was above the norm: in Germany, Czech, Poland, Balkan countries – by 2-3°, in Ukraine, Moldova, Belarus and Baltic countries – by 3-4° and more. Repeatedly in East and North Europe the new temperature maximums were registered. Only in south-west of the continent it was colder than usual: in Spain the anomalies were -2…-3°.
At the opposite coast of Atlantic ocean in USA the cold and warmth withstood each other. The temperature norm in the centre of the country became the result of this struggle, as well as abnormally warmth in the south-west – anomalies +2…3° and abnormal cold in the north-west (states Washington, Oregon, Idaho, Montana) and north-east (from North Dakota to Atlantic coast and Kentucky) – anomalies -2…-3°. Heavy cold penetrated to the north-east in the end of the month. In North Dakota the temperature decreased to -34°. At the Atlantic coast, where it was not so cold, only -10…-15°, but because of high humidity and warm ocean vicinity, the cold was felt heavier. For that matter, it was intensified by heavy snowfalls. Rescuers found frozen corpses of people and animals under the snow. At the Man Gulf coast the stiffen sharks were casted ashore.
Alaska has the special status. It is situated in other climate belt than other country. This time it was extremely warm. The average monthly air temperature anomalies exceeded +9°. December of 2017 in Alaska became the warmest on the record. It was warmer than usual in the most part of Canada: in the centre of the country – approximately by 2-4°, in the north – by 4-6°. Only in the east in Ontario, Quebec, Newfoundland provinces the weather was colder than usual.
The warmest December on the record is registered in Arctic. The record of 1938 is exceeded, which was registered during previous warming in Arctic. In all Arctic region, the average monthly air temperature of December is above the norm: in Russia, Canada and Alaska – by 6-10°.
In the Northern Hemisphere the year of 2017 is abnormally warm. Its average temperature (with the accuracy to 0.1°) is the second among the highest values (together with 2015), succeeding the superiority only to 2016. Except Russia, the last year became also extremely warm in China, repeating the values of 2007 and 2015. In Arctic it became the second (together with 2011), in USA – the third. Average monthly air temperature anomalies in Arctic have set +4…+5°. Except Russia, air temperature norms were exceeded by more than 2° in the south-west of USA and north of Mexico, in the north of Canada, Middle East, in Mongolia and Central China, in the west of Atlantic ocean. In all continents of the Northern Hemisphere the average annual air temperatures are above the norm. It was colder than usual only in some areas of mid-latitudes of Pacific and Atlantic oceans.
In Moscow, the average monthly air temperature in December is 0°. Anomaly is +6.1°. With such temperature the last December gets 4 line among the warmest months on the record, but succeeded to the record December 2016 the noticeable 1°. November and December of 2017 in the capital have the same average monthly air temperature. In December it was not even one day with the below the norm temperature, and the new daily maximums were registered triple times over the month.
 Ocean Surface Temperature.

The main climate event in the ocean is the further strengthening of La-Niña. Area of the negative anomalies of Pacific ocean surface in equatorial latitudes, continues to extend, having get the strong support from cold Peruvian current. Negative anomalies more than 2°, which were observed in November in some places, now they embrace the noticeable part of the equatorial belt in the east of the ocean, and average negative anomaly in this area exceeded 1°.
Negative SST anomalies are concentrated also along the coast of East Asia, in the tropical latitudes of the ocean the very warm water is observed. Here the anomalies exceeded +1°.
In Atlantic ocean Gulf Stream looks strongly. SST anomalies in the Gulf of Mexico and to the north from Florida reached +1° and more, to the north along US and Canada coast - +2…3° and more.


In December, the heavy atmospheric precipitations fell over all European territory. In the each area their monthly sums exceeded the norm or reached them. Heavy rains were observed in the central regions (Ryazan, Ivanovo, Tula, Kostroma), in Upper Volga and Black Sea coast of Krasnodar district. In some areas of Karelia, Murmansk, Novgorod, Ryazan, Oryol, Nizhniy Novgorod, Kursk, Rostov regions the monthly norms were exceeded in 2 times and more.
Urals have got a few precipitations, in some areas only half the norm and less. But Siberia has got a lot of it. Everywhere, except Taimyr, it is more than the norm, in Baikal area even 2-3 times more the norm. Republic of Yakutia, Khabarovsk district, Amur region had a deficiency of precipitations. Here it was only a half and quarter of the norm. But other areas of the Far East: Magadan and Sakhalin regions, Chukchi Autonomous region, Kamchatka district have got a surplus of precipitations. In the end of the month in Kamchatka over the three days it has fallen more than monthly norm of precipitations. In these areas precipitations norms in some places were exceeded in 2-3 times.
China, Korea and Mongolia have got a dry December. It was less the norm of precipitations everywhere. There are areas with absence of precipitations at all. The same regards to the south prefectures of Japan, whereas in the centre and north of the country it was a plenty of precipitations, in some places more the norm in 1.5-2.0 times. In the island of Hokkaido the snow fell.
South-East Asia, as before, was inundated by rains. In Vietnam, Thailand, Malaisia, Philippines the precipitation norm were exceeded in 2-3 times. It caused floods, landslides and hundreds of human losses.
Dry weather was in India. Only in the north-west of the country and in the south of neighbouring Pakistan there were rains.
Kazakhstan has got roughly the norm of precipitations, whereas to the south in the Central Asia republics and Afghanistan it was dry.
It was absence of rains in the Middle East. They fell only in the west areas of the region in Transcaucasia and Mediterranean and Black seas coast.
The same situation was in the North Africa. The rains took place only in Mediterranean area and in some oases of Algeria. Sometimes they were very heavy – up to 50 mm per day.
As well as ETR, Europe has got a lot of precipitations. Heavy rains fell along the Mediterranean coast. In Sicilia over 9 hours the one third of monthly norm has fallen. In this month the snowfalls became a disaster for Europeans. In Switzerland and Germany they caused many kilometres of traffic jams, closure of airports. In UK and France because of sudden deterioration of the weather conditions the increased level of hazard was declared. The snowfall reached even the south of the continent. Greece, Balkan countries and Moldova were covered with snow. According to the European meteorologists’ assessment, there were the heaviest snowfalls in Europe over the last 4 years. In the most part of the continent the monthly precipitations sums exceeded the norms. In some countries: Germany, Austria, Slovenia, Hungary, Romania, Ukraine – in 2 times and more. Only in the south of Italy, in Spain and Portugal the atmospheric precipitations were the very rare thing.
In the most part of USA it was dry weather. Especially it was in the Pacific coast and the central states. In California the absence of precipitations, as before, caused the fires. One of them, named “Thomas”, was recognized as the largest one on the state’s record. It destroyed more than 1100 sq. km of the terrain, which caused the substantial damage to the state’s economy.
Winter snow falls appeared in the south of USA earlier than in the north, which happens very seldom. In Texas, Alabama and Atlanta the snow fell in the first decade of the month, whereas it came to the north only in the end of the month, covered almost the north-east states. Once again Alaska is a special one. It was informed, that the heaviest snowfall on the record fell here. More than two meters of snow have fallen over three days.
In Canada it was a few precipitations, like in USA. Its norm was noted only along Atlantic coast, in polar area and some areas situated along US-Canada border.
In Moscow the monthly precipitations sum has set 86mm, this exceeded the norm in 1.5 times.
In general, the precipitations in most part of the continents have set the norm over the year. North and polar areas of Eurasia, North America, west of China and South-East Asia the precipitations were above the norm. Middle East, North Africa, South Europe have got a deficiency of precipitations. Probably, this is consequence of the global warming, when cyclones paths dislocate to the north. As a result, northern countries have got more precipitations, whereas southern ones are in the arid conditions.