Tomorrow is a Marginal day for much of Europe with a Level 3 hail threat for North Spain and South France and West Italy and South Central Europe with a isolated tornado threat for South France.
A marginal has been issued for North Spain, South France, North France, South Belgium and South Germany for 2 upper trough formations, one over South France the other over Northern Western mainland Europe. This does bring SBCAPE values for most at 1,000 j/kg within the regions with a 2,000 j/kg spike over South France and South Germany with Dew points ranging from 16-20°C, Updrafts look moderate so small to moderate hail will be possible within a few cells but most will miss these although accumulations will be possible. Excessive precipitation is a risk which could lead to some localised flooding. The main hail threat is to the South, the hail parameter shows a large hail possibility over Catalunya but with a strong cap in place it is unlikely any thunderstorms have a chance to initiate if they do they will be elevated bases. A level 1 tornado threat has been issued for South France for SRH 0-3km values ranging from 150-250m2s2 with 0-6km shear at 40kts and 0-1km shear at 15-25kts.
Marginals have been issued for West Italy, South Central Europe into Russia for a chance of severe thunderstorms developing through out the day, SBCAPE values for the majority range from 750j/kg to 1,600 j/kg and in the Mixed Layer CAPE values for many are at 750j/kg with a few spikes at 1,000 j/kg so the storms that do develop could potentially be elevated bases over South Europe. Excessive precipiation is a threat for North Italy, Romania and Russia and in lesser extent for the rest of the marginal area as for the 3 countries PWAT values range from 1.5-1.7″.