Mesoscale Discussion
Valid: Sun 19 Jul 2015 11:00 to Sun 19 Jul 2015 14:00 UTC
Issued: Sun 19 Jul 2015 11:51
Forecaster: GROENEMEIJER

At 11 UTC a warm front was located along a line from near Leipzig to Poznan to Warsaw. An MCS / area of convective rain over NE Germany has created an outflow boundary that stretches from Berlin to Leipzig.

Along the warm front distinct surface convergence is taking place and low-level humidity is rather high with 18-21 C observed dew points. With 26-30 C surface temperatures, around 1000 - 1500 J/kg of MLCAPE should already be in place.

The Bayreuth, Lindenberg and Doksany profilers and Poznan radar confirm that 20-25 m/s WSW winds are in place at 3-4 km AGL, implying that strong to very strong wind shear is present.

Storms, probably elevated have formed in the Leipzig area and further south across the Czech Republic. It is expected that these storms will move eastward and become surface based. It is possible that storms will rather rapidly develop into a squall-line and that the wind risk will increase rather quickly.

In addition, more storms may form further to the east along the warm front after 13 UTC. Any isolated storms that manage to form will quickly turn into powerful supercells with a risk of large hail and severe wind gusts.

The high (about 300 m2/s2) SREH and anticipated strengthening low-level shear that is in place along and slightly to the north of the warm front suggests that tornadoes cannot be ruled out. However, in most places, the LCL height is rather high for tornadoes with T/Td spreads around 10 C, limiting this risk. An exception is a small area along the warm front where prior rainfall occurrs before the arrival of storms, cooling and moistening the boundary layer.