[Source: NOAA Climate Prediction Center, http://www.cpc.ncep.noaa.gov/
The East Atlantic/ West Russia (EATL/WRUS) pattern is one of two prominent that affects Eurasia during most of the year. This pattern is prominent in all months except June-August, and has been referred to as the Eurasia-2 pattern by Barnston and Livezey (1987). In Winter, two main anomaly centers, located over the Caspian ... Sea and western Europe, comprise the East Atlantic/ West Russia pattern. A three-celled pattern is then evident in the spring and fall seasons, with two main anomaly centers of opposite sign located over western/ north-western Russia and over northwestern Europe. The third center, having same sign as the Russia center, is located off the Portuguese coast in spring, but exhibits a pronounced retrogression toward Newfoundland in the fall.
The most pronounced and persistent negative phases of the East Atlantic/ West Russia pattern tend to occur in winter and early spring, with particularly large negative phases noted during the winters and early springs of 1969/70, 1976/77 and 1978/79. Pronounced positive phases of the pattern are less common, with the most prominent positive phase evident during late winter/ early spring of 1992/93. During this 1992/93 winter, negative height anomalies were observed throughout western and southwestern Russia, and positive height anomalies were observed throughout Europe and the eastern North Atlantic. These conditions were accompanied by warmer and wetter than normal conditions over large portions of Scandinavia and northwestern Russia, and by much colder and drier than normal conditions over the eastern Mediterranean Sea and the Middle East. During MAM 1993, the area of negative anomalies over western Russia persisted, the positive anomaly center over northwestern Europe became consolidated, and a negative anomaly center became established over the eastern North Atlantic. These conditions brought a continuation of warmer (colder) than normal conditions to Scandinavia (eastern Mediterranean Sea sector), and drier than normal conditions to much of Europe.