Mesoscale Discussion
Valid: Wed 11 Jun 2014 12:00 to Wed 11 Jun 2014 18:00 UTC
Issued: Wed 11 Jun 2014 12:47
Forecaster: BEYER

Northeastern Germany, westem Poland...
... a mesoscale convective system has formed out of night time convection over northeastern Germany. After a typical diurnal minimum it now is on the way to get better organised. When the system is moving further to the northeast it will meet boundary layer conditions of 25 to 29°C of T2m and dewpoints between 16 and 20 degree. In radar the system is showing some nice features as for instance an enhanced reflectivity on the southern flank.
In the last hour measurements gave 36 mm of precipitation (Neuruppin) and a severe wind gust of 112 km/h (Kyritz). Thus the system is likely to bring severe weather to the highlighted area. Excessive precipitation, marginal to large hail as well as severe wind gusts may occur. Further to the east the system should step by step weaken due to low dewpoints (9 to 12 degree)

Eastern Germany...
... convection has initiated in an area that has a good overlap of humidity and steep lapse rates. Orography and the outflow boundaries of the system described above can hold as a trigger. Convection is likely to continue troughout the afternoon into the evening when it will start to weaken and decay.
Large to very large hail as well as excessive precipitation and locally severe wind gusts are likely having 1000 to 1500 J/kg of CAPE and 0-6 km bulk shear of about 15 m/s.

Massive Central and Alpine Region, Black Forest...
... due to diurnal heating the convective temperature is reached and convection is about to start. Due to a lack of synoptic scale vertical motion, convection is strongly coupled to ororgraphy (mesoscale vertical motion). CAPE is about 1000 to 1500 J/kg as Payerne and Wien soundings indicate. Deep layer shear is only about 10 m/s. Thus pulsating storms and new developments at their outflow boundaries are morst likely. Large to locally very large hail at the beginning oft he cell development as well as excessive precipitation in a later stage are most prominent. But also a severe wind gust can not be ruled out.
Convection should slowly decay in the later evening hours, due to the lack of diurnal heating and synoptic scale vertical motion.