12.12.2018
Climate characteristic of autumn 2018
Average air temperature of the autumn season 2018 was 8,0°С that is 1,5ºС above climate normal.
Deviation of average monthly air temperature of autumn season from climate normal (+6,5 ºС) in the Republic of Belarus
The most positive deviations of air temperature from climate normal were registered in the territory of Grodno region (+1,7ºС on average across the region), the least – in the territory of Mogilev region (+1,2°С on average across the region).
Al three month of autumn were warm, especially September, when average air temperature was 2,9ºС above climate normal. Positive anomaly was 1,3ºС and 0,1 ºС in October and November respectively.
Such warm September with average republican temperature 15ºС was registered for the first time since the post-war period. Very warm weather was in the first and second decades of the month. Temperature increased up to +24+28°С on during daytime hours in the beginning of the month, it reached +30°С in the south of the country on September, 4. Maximum air temperature in September and in autumn (+30,2°С) was registered at the meteorological stations Oktyabr and Pinsk.
Average air temperature and climat for months of autumn season across the Republic of Belarus
Sustainable transition of average daily air temperature through 15ºС was realized on most of the country (except north regions) on September, 22-23 that is 2 decades later than usually. In these dates climate summer ended. Such long climate summer is observed for the first time since the post-war period on the territory of Belarus. Transition of average daily air temperature through 10ºС was realized on most of the country on September, 23-25, at a time close to normal (end of the period of active vegetation). In the south-western areas this transition was realized on September, 29.
Because of cooling by the end of September, frosts were observed in the air and on the soil surface. During this time, frosts in the air are registered in 30-60% of years, on the soil surface more often – 50-70% of years.
Average air temperature in October was 8,0ºС across Belarus that is 1,3ºС above climate normal. Very warm weather settled in mid-October and at the end of the month: air temperature on daily hours exceeded +15°С, on certain days – +20°С. Maximum air temperature (+23,8°С) in this month was registered at the station Polesskaya on October, 7
November temperature was close to climate normal (0,9ºС) and exceeded it only by 0,1°С.
In the first half of month, positive temperatures prevailed during daytime hours along with this air temperature on most of the country increased up to +10°С and higher on certain days. Maximum air temperature was registered at the meteorological station Vysokoye (+17,0°С). Night air temperatures were mainly positive in the first half of the month. It got notably cold since the second half of the month, night air temperatures decreased below 0°С. At the coldest night, air cooled to -10°С -15°С and less on November, 30; absolute minimum of this month and autumn was registered at the meteorological stations Kostiukovichi and Vasilevichi (-19,0°С).
Amount of precipitations in autumn 2018 and climate normal across the regions and Belarus
110 mm of precipitations fall on average in autumn across the country that is 70% of climate normal for season. Shortage of precipitations was observed throughout the entire territory of Belarus, the least of precipitations were in Gomel region – 82 mm (52% of climate normal), most of it – in the territory of Vitebsk region – 130 mm or 74% of climate normal.
Amount of precipitations and climate normal for months of autumn 2018
All the three months of autumn were dry. In September were 82% of climate normal, in October – 78%, in November – 46%.
Precipitations were in the form of rain in September. Rains were in general torrential with thunderstorms and hails (up to 8 mm in Ivatsevichi on September, 24) in some areas.
Precipitations of October were in the form of rain and wet snow, snow cover with a height 1-5 cm was observed on the north-eastern part of the country for a short period (Polotsk and Vitebsk, October, 26). Average date of snow cover appearance is usually first decade of November.
Beginning with the second half of November, snow cover appeared on most of the country and at the beginning of the month – on most of Belarus except the west and south-west regions. Its height ranged from 1 to 8 cm (Kostiukovichi) on the last day of the season, there was no snow cover in some areas of Brest and Grodno regions.
The wind became more intense with gusts up to 15-17 m/s on certain days of autumn. Maximum wind speed (21 m/s) was registered in Slavgorod and Brest on September, 24. Glaze-ice and rime phenomena (dangerous phenomenon was registered in Borisov – diameter of wet snow accretion was 35-84 mm on November, 15-16) were registered in some areas at the end of autumn, glazed frost was on some areas of roads, fogs closed down on certain days.
