The Risk Induced by the Warm Winters in Romania (Applied to the Winter of 2006-2007). Climate variability offers big surprises in the succession of seasons in this country. The past few decades have witnessed situations alien to the characteristics of Romania’s temperate climate. For exemple, the winter of 2006-2007, which according to the history of Romanian meteorological records appeared to be the warmest compared to other warm winters, such as the 1935-1936 and 1947-1948 ones. Local deviations topped 9ºC (the highest values being registered in the Cujmir-Calafat sector, south-west Oltenia). The very low quantities of precipitation, far below normal values, prefigured the drought of the coming year. What caused that situation were the North Atlantic Oscillations (NAO) that persisted for a long time, favouring the penetration of tropical (Saharian) heat waves, and hampering the fall of precipitation, a phenomenon assigned to global warming. If until 1960, warm winters might have occurred once in 10-15 years, after 2000 they would occur every 2-3 years. Were NAO to persist also in the future, there is the risk for warm winters to become increasingly more frequent in Romania.