Storm Forecast Valid: Sat 13 Sep 2014 06:00 to Sun 14 Sep 2014 06:00 UTC Issued: Fri 12 Sep 2014 23:14 Forecaster: PISTOTNIK
A level 1 was issued for the S Baltic Sea and surroundings for excessive precipitation and to a lesser extent for tornadoes.
Level 1 areas were issued for E Germany, W Poland, W Slovakia, E Czech Republic and E Austria for excessive precipitation.
A level 1 was issued for SE Italy, the N Ionian and S Adriatic Sea, Montenegro, E Bosnia-Hercegovina, Serbia and Hungary for excessive precipitation and to a lesser extent for large hail and severe wind gusts.
A level 1 was issued for Albania, FYROM and parts of Greece mainly for excessive precipitation and to a lesser extent for waterspouts.
A level 1 and level 2 were issued for E Spain mainly for large hail and severe wind gusts.
Between the subtropical jet over the southern Mediterranean region and the polar jet over Iceland and northern Scandinavia, a broad "no man's land" covers most of Europe. It is characterized by several compact upper-level lows and otherwise weak geopotential gradients. The strongest upper-level low is stationary near the Slovenian-Croatian border. Warm air advection and a series of pivoting vorticity maxima create lift on its southern and eastern flank from the Balkans towards Poland and continue to induce several surface cyclogeneses. Another small upper-level low - without any signal at low levels - slowly drifts from southern Sweden into eastern Germany. High-resolution models even agree on a third geopotential minimum prowling around over southwestern Poland. The surface pressure field is more homogeneous with a large anticyclone over the North Sea and most of Scandinavia and broad low pressure over the Balkans, the central and eastern Mediterranean region. The mentioned small upper-tropospheric features in the absence of noteworthy surface signals make this forecast particularly tricky.