Storm Forecast
Valid: Tue 22 Mar 2016 06:00 to Wed 23 Mar 2016 06:00 UTC
Issued: Mon 21 Mar 2016 20:58
Forecaster: DAFIS
A level 2 was issued for Italy mainly for severe wind gusts, large hail, tornadoes and to a lesser extent for marginal excessive rainfall events.
A level 1 was issued for the surroundings mainly for a similar risk but with lower probabilities in coverage.
SYNOPSIS
A very interesting weather pattern is found over Europe during this outlook. Several short-wave troughs affect the North Europe with high PV advection and create quite unstable conditions with marginal low topped storms, as well as this cut-off cold pool over Spain, which will eventually fade during Tuesday. Convection-wise the most interesting feature will be a northbound dropping deep cyclonic vortex over the Central Mediterranean and Central Italy during the night.
DISCUSSION
... Level 1 and 2 areas ...
As far as South Italy is concerned, kinematics are impressive for Tuesday, with 25-40 m/s 0-6 km bulk shear and augmented LL shear, especially along the eastbound moving front, overlapping with some hundreds of CAPE. Convective initiation along the front will be marginal due to the formation of CIN, by the LL WAA, so convection will be mostly found over continental parts of Italy after 15z thanks to steep lapse rates. The dry BL does not assist the destabilization, but LL trajectories seem better after 18z in South Italy, with mixing ratios in the range of 9-10 g/kg, where LCLs will be lower and tornado threat increases (LLS 10-15 m/s). One or two multicells could form into this strongly sheared environment during the night, with SREH0-3km up to 600 mē/sē and considering the dry mid level air masses, severe wind gusts are expected. PW values are not high but in the range of 18-22 mm, marginal excessive rainfall events, enhanced by topographic features cannot be ruled out. The aforementioned threats will be found over the Adriatic and Ionian Seas by the early morning of Wednesday, as the depression shifts NE.
