Nuevamente, en zonas del S de Rumanía, Serbia, Macedonia... ojo por que son muy probables supercelulas con granizo grande a muy grande, tornados y lluvia excesiva.
... Macedonia, S Serbia towards Bulgaria and S Romania ...
Ahead of the deepening surface low, tied to the left exit region of mid-level jet-streak, WAA regime will cover much of Bulgaria and S Romania. Here, a warm front is simulated lifting northward during the day. An advection of moist low-level airmass is forecast from the Aegean / Black Sea. In conjuction with pronounced synoptic-scale lift (high values of PVA combined with low level WAA), this setup will create low to moderate degree of latent instability. Furthermore, with mid-level jet overspreading this region, 20 to 30 m/s of DLS is forecast. Thanks to the WAA regime and deepening of the surface low, favourable veering of winds with height will result in long, curved hodographs, as evidenced by forecast sounding from S Romania (featuring SREH over 300 m2/s in the 0-3 km layer).
Overall, conditions will be very favourable for widespread, well organised convection. Especially early into the period, supercells are likely with threats of large to very large hail, severe wind gusts and tornadoes. Due to the strong lift, quick storm clustering is expected with one or more MCS emerging towards the evening, posing primarily risks of severe wind gusts and excessive precipitation. Such MCS will translate towards Central Romania during the night hours, fed by 20 m/s low level jet.
One of the questionable factors is the amount of cloudiness that could limit the daytime heating and also widespread initiation of (elevated) convection early into the forecast period. If both factors apply, severe weather threat could be significantly reduced. Nevertheless, Level 2 seems to be warranted for this region.