WEATHER ANOMALIES IN LATVIA, 2012

The 2012 average air temperature was + 6.1ºC (0.4 degrees above normal period of 1961-1990), putting it in the middle of the long term data row. In the 21st century year 2012 was the second coolest (Fig.1).

The months of the year 2012 in terms of the temperature’s deviation from normal were mostly moderate (Fig. 2). None of the months was among the ten warmest or coldest in corresponding long term data series. Even February with an average temperature of -8.8 °C was only the 14th coldest.

For the sixth consecutive year the rainfall in Latvia was above normal. With a yearly precipitation amount of 832 mm (127% of normal) the year 2012 was the 4th wettest in the last 90 years and the second wettest in the 21st century (Fig.3).

In 2012, in ten months of twelve, the precipitation amount was above normal. The precipitation from December 2011 to July 2012 was continuously above normal (Fig.4). Such a long precipitation-rich period (8 months) was recorded for the first time in Latvia’s precipitation measurement history.

The winter of 2011-2012 average air temperature (-3.4°C) was 0.9°C above the 1961-1990 normal. Warm December in 2011 was compensated by a mostly cold February in 2012, in which a continuous, 5-day long, period of severe frost below -30ºC was experienced. Usually such a low temperature in Latvia lasts for only one – two days. Before 2012 continuous periods of five and more days of severe frost below -30º were registered only twice – in February 1996 and in February 1956.

All the winter months of 2011-2012 were rich in different types of precipitation, thus the winter in total was the wettest in the last 90 years in Latvia. Its amount of precipitation was 210 mm (176% of normal). 

The spring average temperature was 1.4ºC above normal, precipitation amount – 133% of normal. Summer was close to normal: temperature 0,3ºC above it and precipitation -112%.

The autumn average temperature was 1.3ºC above normal, precipitation amount – 125% of normal. Unusual weather contrasts were in the second half of October. With the daily average air temperatures 6ºC above normal, 19th and 20th October were the warmest corresponding dates ever registered. Towards the end of the month the temperature dropped and on 27th October snow height in some parts of Eastern Latvia was up to 35 cm. Such thick snow in October in Latvia is rare - on average once every 20 years.