A high pressure field was spreading from the Atlantic towards the western Mediterranean resulting with pronounced pressure gradients over the Alps. Over the Adriatic Sea, mean sea level pressure field was almost uniform – thus no pronounced winds were blowing over the Adriatic Sea. At the 850-hPa level, warm air mass was advancing from the northern Africa across the central and eastern Mediterranean towards the Adriatic Sea. As a result, temperature gradients were pronounced over the middle Adriatic at the 850 hPa height. An upper level trough can be seen at the 500 hPa level – associated mid-tropospheric strong winds (up to ~40 m/s) of southwesterly direction blew at its front side, over the western Mediterranean and the Adriatic Sea.