Jack92jk last edited by pavelneuman
Storm forecast valid Thu 20 Jun 2019 00:00- Fri 21 Jun 2019 06:00 UTC
An important low pressure centered in the North of the British Isles determines the establishment of currents from the south/ south west, in the medium atmosphere, over most of central and eastern Europe.
In this unstable flow, during the day tomorrow, a cold front will move really slowly favoring the formation of strong thunderstorms with very low translation speeds.
The cold front will reamain almost stationary between east Germany, Poland, Austria and Czechia.
France, Spain, Italy and Swiss
In the morning some storms will form in the south east part of France towards south west Germany. The thunderstorms will be organised along a line and they will produce heavy rain and locally strong winds.
Also in the afternoon the storms will move from France towards Swiss and south west Germany, the low directional shear will not support a supercell formation and the storms will be weak.
In the other countries the storm will develop in the afternoon, especially over the moutain regions.
Germany, Czechia, Poland and Austria
The most intense thunderstorms will develop in these regions where the thermal contrast between the Atlantic and African air will be greater.
ml-cape is estimated around 1600-2000 J/Kg, the absence of a high directional shear will favor the development of multicells or squall lines with very big hail and strong winds, but supercells are locally possible, especially between south east Germany and Austria.
The thunderstorms will form between afternoon and late evening.
These regions will have disorganized convection but placed in a context with a lot of Cape. The thunderstorms will form during the afternoon hours and they will be able to produce hailstone.