Mesoscale Discussion

Mesoscale Discussion
Valid: Mon 08 Aug 2022 08:00 to Mon 08 Aug 2022 10:00 UTC
Issued: Mon 08 Aug 2022 07:50
Forecaster: TUSCHY

A MESOSCALE DISCUSSION was issued for most of Italy to highlight the chance for numerous slow moving thunderstorms during the afternoon hours.

A vorticity maximum, currently placed near Genoa, moves SE towards Florence during the afternoon hours with otherwise weak mid-level height gradients over most of Italy. Overall lowered thickness compared to the previous days should support diurnal CI as sea breezes evolve beyond noon.

SSTs of 28-30 C between Corse/Sardegna and Italy with SST anomalies aoa 2-3 K should support rich 2m dewpoint advection well inland with yesterday readings along the coasts in the low to mid twenties. Yesterday's LIRF sounding (Roma-Fiumicino) sampeled this air mass with more than 3.5 kJ/kg MUCAPE during peak heating. Similar peaks are forecast for today with 1-2 kJ/kg well inland. DLS resides in the 2-8 m/s range.

Expect scattered CI along the mountains in the 11-12Z time frame with a general tendency for slow eastward motion due to very weak SW-erly background flow in the steering level. Before any cold pool driven motion sets in, quasi-stationary storms pose a risk for isolated large hail and mainly excessive and locally flash flood producing rain. Convection weakens around sunset while moving offshore towards the Adriatic Sea.

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