Drought in SE Europe - current status and outlook

       This year has again brought drought conditions to SE Europe. According to media reports there were hundreds of human casualties due to exceptional heat wave in Hungary, Romania, Moldova and Greece. Information from Greece quotes the heat wave to be the worst in last 110 years; existence of some animal species (birds) are in danger. Lack of snowfall in Romania in Bulgaria in winter and spring time has caused drought destroying more than 1.7 million hectares of cereal crops. The cotton harvest in Turkey is in danger, first estimates show 50% drop. Drought in Albania continues from the winter and is causing major problems in energy production. Temperatures that are persistently higher than 40 degrees C are causing wood fires in Serbia, FYR Macedonia, Greece and Bulgaria.
       The drought conditions are present over most of SE Europe; they differ among regions in their nature. According to the Global Drought Monitor (http://drought.mssl.ucl.ac.uk) a very persistent drought (assessed over the last 9 month period, which is mainly correlated to ground water levels) is affecting Greece and NW part of Turkey. Drought assessed over 3 and 6 month period (correlated to low stream flows and agricultural drought) has been detected over Hungary, Romania, Bulgaria, Moldova and Greece.

        Most of the regions are suffering from the heatwave conditions which have weakened during the 4th week of July in most of the region. According to sources from forecasting offices, the cooler air mass will continue to propagate over the region and will bring some relief; it is not very likely that such strong anomalies will appear again in the following weeks.
       According to seasonal to inter-annual forecasting products which are provided to meteorological community by global-scale producing centers (listed on WMO web page on ensemble prediction systems - http://www.wmo.ch/web/www/DPS/EPS-HOME/eps-home.htm#Long-range) the predominant weather pattern is not likely to change in late summer and early autumn (August-September-October). Due to the nature of seasonal forecasting systems, which are able to provide only probabilities of predominant weather type during the season, we cannot expect exact forecast, only weak signal on probabilities of average weather type.
       The IRI institute predicts slightly larger probabilities for temperatures to be above normal mostly in the southern part of the region whereas there is no signal for rain anomalies. Similar forecast is issued by the UK Met Office; their categorical forecast simply states that the region is likely to be warmer than average whereas there is no signal for the precipitation. Less favorable conditions are forecasted by ECMWF; in NW and E parts of the SE Europe probabilities for precipitation in the lower tercile of the distribution reach values between 50% and 80%. Similar pattern is forecasted for probabilities of temperature in the upper tercile.
       However, one must be very careful while using seasonal forecast in extratropical region. The skill of the forecast is generally low; information on forecast skill of their products is provided by the UK Met Office forecast next to the forecast charts.     

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