Europe: Water deficits in Finland, surpluses forecast for western European Russia

28 March 2017

The Big Picture

The 12-month forecast period from December 2016 through November 2017 indicates a predominance of water deficits in Western, Central, and Northern Europe and the Baltics, which may reach exceptional severity in Denmark, southern Sweden, Finland, Estonia, and Latvia.

Water surpluses are forecast in eastern Romania and along southern Spain’s Mediterranean coast.

Impacts
Officials in southwestern France's New Aquitaine - the largest administrative region in the country - are beginning to worry about the prospect of drought next summer. The region has been dry for the last six months with rainfall deficits reaching 50 percent in the north, the largest since 1960. River flows are low and reservoir levels are below 50 percent of capacity.

In northwest France drought has led to water restrictions in Ille-et-Vilaine, Brittany where winter rain deficit is estimated at 50 percent. The prohibition covers washing cars, houses and roads, and filling pools. Likewise, the prefecture of Haut-Rhine, Alsace in eastern France is recommending that water use be restricted to essential services, with one community resorting to tank deliveries of drinking water.

The level of Italy's Po River is currently about the same as it was in August 2016, raising drought alarms, and Lombardy region's Civil Protection agency has issued a notice for risk of forest fire. Reservoirs in the north are low: Lake Maggiore is 39 percent, Lake Iseo 24 percent, and Lake Como just 14 percent.

Spain's Costa Blanca in Alicante region on the Mediterranean has experienced its wettest winter in 116 years, where the city of Alicante recorded nearly half its annual rainfall in 24 hours. Fire brigades were enlisted to pump 20,000 cubic liters of rainwater out of buildings in San Juan and 360 residents were without running water and electricity. Almost 200 millimeters (7.87 inches) of rain fell in San Vicente del Raspeig in one day, flooding streets and closing schools.

Forecast Breakdown
The 3-month composites (below) for the same 12-month time period show the evolving conditions.

Noticeable in the March through May map is the emergence of widespread surpluses in western European Russia – indicated by the large blue area. Surpluses in this area may reach exceptional intensity near St. Petersburg and to the east. The opposite condition is forecast for Finland, Estonia, and much of Latvia – exceptional deficit. Severe to exceptional deficits are also forecast in southern Sweden and Denmark. Much of Western and Central Europe is forecast to experience scattered moderate deficits, with pockets of severe to extreme deficits projected for central Germany, southern Austria, Macedonia, and from Rome to Palermo, Italy. Surpluses are forecast for Switzerland and eastern Romania. Near-normal water conditions are expected in the United Kingdom and Ireland.

The June through August forecast indicates primarily moderate deficits throughout most of Europe with widespread exceptional deficits persisting in Finland and Estonia. Moderate to extreme deficits are expected to emerge in southern Norway and will persist in southern Sweden and in Denmark. Switzerland is forecast to transition from surplus to moderate deficit. The pink area in Russia indicates both deficits and surpluses as surpluses recede and deficits emerge.

The overall pattern of anomalies for the final months of the forecast period – September through November – indicates primarily low intensity deficits throughout most of Europe.

(It should be noted that forecast skill declines with longer lead times.)