Country sees severe night frosts, heat wave in June

The last month June got off to a chilly start, which was followed by extensive heat, according to the Finnish Meteorological Institute (FMI).

There was less precipitation than usual in June in nearly all parts of the country, said the FMI in a press release on Friday.

According to FMI, June was one to two degrees Celsius warmer than usual in most of the country. The greatest deviations were observed in the southwest archipelago and in the Åland Islands, where the average temperature was two degrees higher than normal, which can be seen as rare.

In northern parts of the country the average temperature varied between 10°C and 15°C and in other areas the variation was 14–17 degrees Celsius.

The early days of the month was unusually chilly. At some observation stations, occurrences of night frost, when the temperature at ground level falls below freezing, set new records for June.

After the cold start, hot conditions dominated later in June. Starting from 12 June, high temperatures of 25.1 degrees Celsius or more occurred somewhere in the country every day.

In a typical June, such levels of heat are reached on eight days of the month, but this year the hot-weather threshold was crossed on 19 days. The number of hot days was above average in almost all parts of Finland. In western and southern parts of the country the number of hot days was unusually, or exceptionally high. On two days, the temperature exceeded 30 degrees Celsius.

The highest temperature for June, 31.6 degrees Celsius , was recorded at Niinisalo Airport in Kankaanpää on the 20th of the month. The lowest temperature for June, minus 7.7 degrees Celsius , was recorded at Saana Fell in Kilpisjärvi on the first of the month. It was the lowest temperature ever recorded in June in the history of keeping records in Finland.

There was less precipitation than usual in June in nearly all areas. In many parts of the west and north, precipitation was less than half of the long-term average level for June. Helsinki-Vantaa Airport had the lowest precipitation level ever recorded for the month 5.6 millimetres. Higher than average precipitation was recorded mainly in parts of North Karelia.

According to preliminary information, the location with the greatest amount of precipitation was Mekrijärvi in Ilomantsi, which got 100.6 millimetres of rain.

The least precipitation for June was recorded at the Kumpula observation station in Helsinki – 2.6 millimetres. The highest amount of rain measured in a single day was 55.7 millimetres at the Möksy Observation Station in Alajärvi on 22 June.

There were more hours of direct sunlight than usual in much of the country. On the south coast and in the archipelago, the amount of sunshine was unusually or exceptionally high (370–420 hours).

The beginning of the month continued what had been a period of low thunder activity, but at the end of the month, on 28 June more than 10,000 cloud-to-ground discharges, and more than 9,000 on 29 June.

The total number of cloud-to-ground discharges for the entire month was 43,500. The average number of cloud-to ground discharges for the normal period for June is about 34,500.