MAIN WEATHER AND CLIMATE TRAITS IN THE NORTHEN HEMISPHERE AS OF MARCH 2020

Air Temperature

March in Russia has always been considered a cold month. Indeed, frosts below -10° in the European territory and below -20° in the Asian territory have been commonplace in March for a long time. Yet the air temperature in March has remarkably increased over the recent years, and the events of unprecedented warmth started to follow one another at a high rate. Thus, March 2017 became the warmest in the history of meteorological observations in the country while March 2019, the third warmest in the ranking list. Extremely warm winter of the last year naturally suggested that this tendency would persist. But what happened in reality surpassed all expectations: the average temperature in each decade of the month exceeded the normal value by 8° to 12° or more in various regions. No territories exhibited sub-normal temperatures with the exception of some far north-eastern locations in the first decade. Eventually, the monthly-averaged temperature in most of the country turned out to be 6-8° or more degrees higher than usual. New maxima of air temperature were recorded in the north-west and centre of the country, in the Volga Region and in the Northern Caucasus, in the Crimea, Siberia, Yakutia, Kamchatka and Chukotka. March 2020 became the warmest in the history of meteorological observations in the ETR and in the Volga and South Federal Districts in particular, the third warmest one in the Asian territory, and the second warmest in Russia as a whole – outranked by March 2017 only. The monthly-averaged temperatures in all federal districts entered the Top Ten of highest values in the meteorological chronicle.
Abnormally warm weather occupied all of East Asia as well. The monthly-averaged air temperatures were 3-6° higher than normal in Mongolia, and 2-4° higher in China where their value averaged over the whole country was the fifth highest in the history of meteorological observations. This March was the second warmest in Hong Kong.

Temperatures above the normal value also prevailed in South-East Asia where the normal monthly averages were exceeded by 1-2°.
In India, the monthly-averaged temperature was normal or even slightly lower than that.
The warm weather set in Russia was also observed in all Central Asia. The normal values of monthly-averaged air temperatures were exceeded by 3-8° in Kazakhstan, by 3-5° in Uzbekistan and Kyrgyzstan, and by 2-3° in Tajikistan and Turkmenistan.
In the Near and Middle East, the temperature was also above normal, by 1-2°.
A similar picture was observed in North Africa: the anomalies of monthly-averaged temperature were +1…2° or more in Algeria, Tunisia, Senegal, Mali and Niger.
The weather in Europe was also abnormally warm. This is especially true for the eastern and central parts of the continent, where the anomalies of monthly-averaged temperature were 2-4° or higher. In the east, new daily temperature maxima were recorded in some places. But on the last day of March, the Arctic cold encroached. Extremely low temperatures were recoded in Czechia on that day, as low as -20° in the mountains. The daily minima were recorded in Belarus and Ukraine.
Most of the Western Hemisphere was also basking in warmth. In the US, this March entered the Top Ten of the warmest ones in the history of meteorological observations. The temperatures were notably high in the east and centre of the country. The monthly-averaged temperature everywhere from Texas and Oklahoma to Virginia and Florida was among the five highest in history: there, the anomalies reached 2-4° and more. At the same time, this temperature was normal or sometimes even 1-2° lower than that in the North-West and in the western provinces of Canada. Abnormally warm weather persisted in Mexico and all over the Caribbean. The normal values were exceeded by 3-4° in Mexico and by 1-3° in Central America and on the islands.
Such warmth almost everywhere in the Northern Hemisphere affected, in particular, the average temperature over there. The latter was ranked the second highest in the history of meteorological observations, and was lower than in March 2016 only when it was just 0.1° higher.
In Moscow, the monthly-averaged air temperature in March was +3.8°, and the anomaly was +6.0°. This March was the second warmest in the meteorological chronicle of the capital, only March 2007 being even warmer, by 0.6°. Six new daily maxima of temperature were recorded in March 2020.

Ocean Surface Temperature

The surface temperature of the oceans in the Northern Hemisphere remained very high. In the Atlantic Ocean, its value averaged over the whole area reached the second extremum (+0.6°) and was just 0.1° less than the absolute maximum observed in March 2004 and 2005. The temperatures were especially high in the equatorial belt from South America to Africa as well as in the Gulf of Mexico, along the US coast and in the separated water bodies further eastwards. There, the anomalies were higher than +1…2°. Water in the northern part of the ocean was abnormally cold, but the surface temperature was above-normal in the marginal seas, namely, the North and Baltic seas.
In the Pacific Ocean, the anomaly averaged over its entire area retained the value of +0.5° that was observed in the first months of the year. As in the Atlantic Ocean, large positive anomalies took place at subtropical and tropical latitudes, including the coast of China, Japan and Russian Primorye (+1.0° or more), and large negative ones, in the north, i.e., in the Sea of Okhotsk and in the Bering Sea, and along the coast of North America. The phase of the Southern Oscillation remained neutral.

Precipitation

Precipitation in the ETR was abundant in the northern regions, and scarce in the southern ones. The normal precipitation amounts in the North-West Federal District were exceeded by about 1.5-2.0 times or by larger values in some places. The monthly precipitation totals reached the record-breaking figures in Karelia and the highest values for the last 25 years in Saint-Petersburg. Heavy rains poured in the north of the central region, bringing up to half the normal monthly amount of precipitation per day in the second decade.
In contrast, the precipitation amounts were low in the regions to the south: less than half the normal value everywhere. Precipitation was in the form of snow sometimes. For example, the snowfall descended on the blooming Stavropol Territory in the middle of the month and created a temporary snow cover up to 5 cm high. In the third decade, a similar phenomenon was observed in the Crimea and in the Rostov Region. On the last day of the month, snow cover was partially restored in the Central Russia and in the Volga Region, but the Northern Caucasus was hit by showers that brought up to 40 mm of rainwater per day.
In the Urals and to the east of them, a lot of precipitation was observed: up to 1.5-2.0 times the normal amount in some places. The unprecedented snowfalls and blizzards stormed in the Kamchatka, Chukotka, Kolyma and Sakhalin. Sometimes they contributed up to 15-20 cm to the snow depth in just one day. In Petropavlovsk-Kamchatski, a new daily maximum of precipitation in the city was recorded. The normal monthly precipitation amount was exceeded as early as by the middle of the month.
The weather in Mongolia and in the north of China was common for this time of year. However, rains were plentiful in the central and southern regions of China where their amounts were normal or increased (by 1.5-2.0 times in places).
Heavy rains came to South-East Asia. In Vietnam, Thailand and on the Indonesian island of Java, they caused severe floods resulting in significant damages to agriculture. Fatalities were reported. The normal precipitation amounts in these countries were exceeded by 3-4 or more times.
The month was very rainy in the north of India were the precipitation quantities were 2-3 times larger than usual. According to the meteorological service, March 2020 in Daily was the rainiest one in the meteorological history of the city. Though, it was dry in other regions of the country.
Dry weather prevailed in Central Asia. The monthly precipitation totals amounted to just several millimetres in Kazakhstan, and to slightly larger figures in the Middle Asian republics, less than 10% of the normal value as a rule. Yet, heavy showers ran hit the Afghanistan in the last days of March to result in massive floods. Human deaths were reported there.
The distribution of precipitation was diversified in the Near and Middle East. The precipitation amounts were normal or increased in Iran and the Levant countries, but almost no rains went to the Arabian Peninsula except for Yemen where a heavy shower caused massive flooding on the last day of the month. At the same time, heavy rains passed along the east of Syria. Flooded rivers overflowed their banks, landslides were triggered, people died, and the transport infrastructure was partially destroyed.
The weather was dry in North Africa. Rains were only observed along the Mediterranean coast and in the Gulf of Guinea. In the west of Kenya, floods were caused by heavy showers.
In Europe, rains drummed in the west and east of the continent. The normal precipitation amounts were exceeded by 2-3 times or more in Spain where this March was the seventh wettest in the history of the country, and new daily or even monthly maxima of precipitation totals were recorded. The anomalies of precipitation were roughly the same in the Balkans and the Baltic. But in the areas between the south of Germany and the north of Italy or from eastern France to Poland, Czechia and Hungary, less than half the normal monthly precipitation quantity was recorded as a rule.
The monthly precipitation totals were close to normal in most of the USA and Canada excluding some regions where they were 2-3 times higher: Texas and California in the USA and the polar region in Canada. On the other hand, some regions received scarce precipitation, namely, the states of Washington and Montana in the USA, and the province of British Columbia in the west of Canada or the northern Quebec in its east. Almost no rains were observed on the islands of the Caribbean.
In Moscow, 51 mm of precipitation accumulated during the month; this amounts to 1.5 times the normal figure. Precipitation was particularly abundant in the first half of the month. For example, a new maximum value of daily precipitation totals was recorded on March 10, and the normal monthly precipitation amount was already exceeded by March 17.