The key weather and climate features in the northern hemisphere in September 2015

Air temperature

Extremely warm weather was maintained in European Russia in the second half of September. Numerous daily maximum temperature have been recorded from Novaya Zemlya to the North Caucasus. The thermometer repeatedly rose above +30°C, which was a rare event even during the last summer in European Russia. Average air temperature in the third decade of the month exceeded the norm by 4-9°C, while on a monthly basis - by 3-5°C. Nature vividly reacted to such a warm weather. In the south, there were flowers on apple and the lilacs bloomed for the second time in a year. In Crimea, last September was the warmest in the history of meteorological observations. In the Russian north, the south of Russia and in the Volga region, it was the third warmest one. Such heat was not seen over the last 20 years; the records belong to the mid-30s of the last century. On the last day of the month freeze reached the Black Earth region. At night, there were recorded temperatures from -1°C to -3°C.

 

It was abnormally warm in the Russian sector of the Arctic. In northern Evenki and Yakutia, as well as on the Arctic islands the daily maximum temperature was exceeded and monthly mean values have surpassed the norm by 2-3°C or more.

 

The cold in September reigned in the south Urals, and in most parts of Siberia. In Omsk, Tomsk, Novosibirsk, Kemerovo region at night frosts reached -4 ... -6°C. The weather was more in line with the middle of autumn, rather than the beginning. Average temperatures here were 1.0 ... 1.5°C below normal.

In the Far East in the first 20 days of the month, it was relatively warm, but in the third decade the cold has arrived. In the Khabarovsk Territory were recorded even daily temperature minima In Primorye frosts reached -7°C. As a result, the monthly mean values generally corresponded to the norm.

In most of China's temperature background was close to the norm. Only in the northeast of the country, it was exceeded by 1.0-1.5°C.

Average air temperature was above normal in India as well as in most countries in Central Asia. In Turkmenistan, Uzbekistan, western and central regions of Kazakhstan, the hot air with a temperature of 30-35°C acted out of Arabia and Iran. It exceeded the norm by 1-2°C. At the same time in the east of Kazakhstan it was colder than usual. There were freezing to -5°C, and by an average for the month, it was colder than norm by 1-2°C.

Summer heat continued in the Middle East. It exceeded the norm by 1-3°C or more. In Tbilisi, the average monthly temperature anomaly of + 3.3°C, Beirut - + 3.5°C, Baghdad - + 3.8°C, Istanbul - + 4.0°C.

A similar picture was in the northeast of Africa. In Egypt, Libya, Tunisia it was hotter than usual by 2-4°C; the rest of the temperatures generally corresponded to norm. Only in the north of Morocco and Algeria during the month prevailed cool weather.

Western and Eastern Europe in September turned out to be opposites. In the east of the continent continued hot summer. In Belarus, Ukraine, Moldova, the thermometer often rose to + 30°C and above. Were registered new records. It was hotter in the Balkans - up to 35°C or higher. As a result, to the east of Germany, Austria and Slovenia, the air in the average for the month warmed to 2-5°C above normal. In Warsaw and Belgrade anomaly + 2.3°C, Sofia - + 2.5°C, Vitebsk - + 3.0°C, Odessa - + 3.5°C, Kharkov - + 4.4°C. In Western Europe the long summer heat gave way to the early cool. Sometimes it had even more in common with the middle of autumn. In western France, northern Spain and Portugal the temperature during the month was colder than usual by about 1.5°C. In Gibraltar, the average temperature anomaly was -2.7°C. However, in most of Western Europe the temperature was conformed to the norm, although it was at the negative background.

It was very warm on the North American continent in September. In the US, it was the warmest September for 125 years of weather observations. In most parts of the country the rate of temperature was exceeded by 2-3°C or more. In Las Vegas anomaly + 3.9°C, New York - + 3.2°C, Kansas City and Chicago - + 2.5°C. The only states in the country, where last

September was marked by mostly cool weather was Alaska.

In the southeast of Canada temperature of the air was for 4°C above the normal, at the rest of the country it was usually higher than the norm by 2°C or more. Only to the west, along the Pacific coast and in the Yukon, in September the weather was cooler than usual.

In the Arctic, September 2015 was the third warmest in the meteorological record. In the Russian sector of the Arctic and in northern Canada over the last month the average temperature exceeded the norm by 2°C or more. The area of the Arctic ice cap at the end of the warm period, i.e. about the middle of September, reached the fourth all-time minimum of satellite measurements. In comparison with the norm, it was 1.8 million sq. km smaller. Experts note that the melting ice in the Arctic has accelerated dramatically in the last 20 years.

September 2015 in the Northern Hemisphere was the warmest in the entire 125-year history of regular meteorological observations on the planet. Its average temperature surpassed the previous achievement established in 2005; at the same time, the norm was exceeded by more than 1°C. In the fifth month in a row (from May to September), the average temperature of the hemisphere reached a record high.

In Moscow, the average temperature in September + 13.8°C, anomaly of + 2.8°C. This is the fourth result in September since 1891. During the past September, in the capital there were recorded four new daily maximum temperatures.

The temperature of the ocean surface

In the equatorial and tropical latitudes of the Pacific Ocean in the Northern Hemisphere continued strengthening of El Niño. Its influence on the large-scale variability of the average surface temperature (AST) is huge. In the eastern part of the ocean AST anomaly was exceeded by 1-2°C. It affects the average temperature of the ocean surface. In August, it repeated the absolute maximum for the month for the first time for 10 years. Negative AST anomalies were observed only in the east of Japan, and partly in the Yellow, Japan and the southern Sea of Okhotsk.

The positive anomaly enhanced in the Atlantic Ocean. Average sea surface anomaly has increased in two times in comparison with August and amounted + 0.6°C. Still above the norm by 1-2°C was the temperature of the water in the Gulf Stream. In polar latitudes along the coast of Scandinavia and the southern Barents Sea ocean surface warmed by about 1.0 - 1.5°C above normal. But nevertheless, in most of the ocean the temperature conditions were close to normal. In the east temperate latitudes along the coast of Europe had happened at the negative background.

Precipitation

In European Russia after the dry August, with the beginning of September came the rains. In a number of areas already in the first decade fell monthly norm of precipitation. Then came the dry "Indian summer", which lasted almost to the end of the month. As a result, in all federal districts of European Russia there were areas where the amount of precipitation in the past month have not reached even the norm. In the North-West Federal District these areas are Leningrad, Kaliningrad, Murmansk region and the Republic of Karelia; in Central - Ryazan, Kostroma, Ivanovo, Vladimir, Lipetsk, Tambov, Voronezh, Belgorod region. Deficit rainfall occurred across the Volga, Southern, North-Caucasian and Crimean federal districts, except for the Republic of Tatarstan and Kalmykia.

Little rain went to the Urals; to the east in Siberia, they have been almost everywhere. Tomsk, Novosibirsk, Kemerovo Region, Altai Krai and Altai Republic had 1.5 of monthly rainfall and more. In separate areas there were up to 3-4 norms. Only in the Trans-Baikal region was felt the relative scarcity of rainfall.

In the Far East, norm of precipitation and more went to Khabarovsk and Kamchatka, Magadan and Sakhalin regions, partly Republic of Yakutia. It was dry in Primorye.

To the east of the Urals, it was already snowing. In some places in the Tomsk and Kemerovo region, Krasnoyarsk and Yakutia formed snow cover; there were first drifts in the Khanty-Mansi Autonomous District.

The abundant rainfall went to China. In some provinces in the center and east of the country monthly norm of precipitation was exceeded by 3-4 times. Downpours destroyed roads; there were power outages in some areas. Hunan Province was especially damaged: it was even necessary to conduct partial evacuation of the population. Typhoons plagued Japan. They caused widespread flooding in central and northeastern parts of the country. A large part of the island of Honshu was flooded.

The government offered temporary evacuation of over a million people. In separate areas in a few days fell out up to 600mm of rain, the monthly norm was exceeded by 1.5-2.5 times.

Mainly norm of precipitation went to countries of Southeast Asia. In separate areas of Thailand, heavy rains caused massive mudslides and flooding. Popular resort of Pattaya was under the blows of the elements.

The rainy season in India ended with a deficit of rainfall in most parts of the country. Only in the east downpours still continued in September. In Assam, they led to massive flooding caused by overflows of the main water artery of the country - the Brahmaputra and its tributaries. More than a million people were left homeless, dozens of people died under the water.

The weather was dry in the Middle East. The long period of dryness and strong winds led to a long and strong dust storm in Israel. For a week the country was covered with a veil of dust, through which the sun was barely visible. Local meteorologists have argued that this is the strongest dust storm in the history of the State of Israel.

The weather was mostly dry in Africa. Only in the north of Morocco and Algeria, downpours have led to large monthly sums of precipitation, which sometimes exceeded the norm by 2-4 times.

In Europe, there were areas where the rainfall in September was much. These primarily include the southern countries. Heavy rains were in southern France, Spain, Italy, Greece and the Balkans. During the day might fall out up to 100 mm of precipitation. Heavy rain almost washed away the Greek island of Skopelos in the Aegean Sea. In northern Italy, heavy rainfall caused floods and landslides, one of which was up to 30 meters and blocked the road in the area of Venice. There were reports of deaths. In these regions, the continent's norm of precipitation in some places exceeded by 3-4 times. There were heavy rains in Scandinavia and in several countries in Eastern and Central Europe. There norm of precipitation were exceeded by approximately 1.5 times. At the same time, it was dry in Germany and eastern France.

In most of the United States September was dry. The drought continued in California. Due to the dry and hot weather, the air temperature exceeded 30-35°C, many areas were covered by fire. However, heavy rains still occasionally visited the country. In the mountainous Utah per day fell up to 50 mm of precipitation, which caused flooding, people died. About norm of precipitation went to the eastern states of the country, to the northeast - even more.

In most parts of Canada was normal rainfall. Only in the northwest of the province of Yukon, as well as in neighboring Alaska, precipitation sometimes have surpassed the norm 3-4 times, while in the southwest in British Columbia – rainfalls gleaned the norm for about the half.

In Moscow in the past month fell 88mm rainfall, which is 135% of the norm.