Storm Forecast
Valid: Wed 15 Apr 2026 06:00 to Thu 16 Apr 2026 06:00 UTC
Issued: Tue 14 Apr 2026 13:58
Forecaster: TUSCHY

A level 1 was issued for far NE Algeria/NW Tunisia mainly for heavy rain.

A level 1 was issued for W Italy mainly for isolated hail and gusts.

SYNOPSIS and DISCUSSION

Ridging and extensive anticyclones dominate the weather over most of Europe. One exception is the quasi-stationary cut-off over/just W of Sicily and a progressive upper trough over NW Europe, which swings from Ireland N towards Scotland.

Scattered thunderstorms occur beneath the cut-off over the S-CNTRL Mediterranean with MUCAPE in the 400-800 J/kg range and 10-15 m/s DLS in place. A few organized thunderstorms are possible W of the Apennines (provinces Lazio and Campania) with isolated hail, strong gusts and locally heavy rain. Point-source forecast soundings from this area show local MUCAPE peaks up to 1000 J/kg with DCAPE up to 700 J/kg, which is plenty of energy for isolated hail up to 2 cm in diameter and a few strong downbursts. A marginal level 1 was added.

Next to the vortex' core we expect numerous slow moving showers/thunderstorms, which affect far W Sicily with patches of heavy rain. This is too marginal for a level area.

A rainfall driven level 1 was added for extreme NE Algeria/NW Tunisia, as moist and slightly unstable onshore flow interacts with the E-Tell Atlas/Aures Mountains. 24h rainfall amounts up to 100 l/qm/24h are possible with local flash flooding expected.

Over NW Europe, a moist postfrontal airmass offers up to 500 J/kg MUCAPE as temporal diabatic heating kicks in from the SW. Strongest storms may pose some graupel and gust risk, although the combination of a moist airmass with low LCLs and improving 3CAPE could also support a funnel/short-lived tornado event mainly over E/N Ireland and W/SE UK. The risk abates after sunset and the magnitude of the severe risk does not justify a level issuance.