Storm Forecast
Valid: Tue 02 Nov 2021 06:00 to Wed 03 Nov 2021 06:00 UTC
Issued: Mon 01 Nov 2021 22:36
Forecaster: DAFIS
A level 1 has been issued for W France mainly for severe convective wind gusts.
A level 1 has been issued for parts of Italy and W Mediterranean for excessive convective rainfall and severe convective wind gusts.
A level 1 has been issued for Albania and W Greece for excessive convective rainfall and severe convective wind gusts.
A level 1 has been issued for E Greece and W-S Turkey for excessive convective rainfall and severe convective wind gusts.
SYNOPSIS
A deep trough is forming in western Europe, surrounded by several vorticity maxima, and results in a strong jet stream over the Mediterranean. The jet increases the shear in S Europe substantially, increasing the threat for severe weather events where storms develop. CAPE is mostly found over the sea, so coastal and insular areas will be mostly affected by storm activity on Tue 2/11.
The subtropical storm (and former medicane) "Apollo" has now weakened significantly before reaching the Turkish coasts but strong low-level convergence and high instability with strong shear have led to the development of supercells in eastern Mediterranean.
DISCUSSION
.... W France ....
A short-wave trough with a jet streak is forecast to cross western France in the afternoon, and some instability is expected over the Bay of Biscay. Strongly sheared storms can pose a threat to the coasts as convective wind gusts may exceed 20 m/s. Showers are also expected from fast moving storms.
.... W Mediterranean and Italy ....
A strong zonal flow is about to be established in this part of Europe, where a mid-level jet will exceed 30 m/s in wind speed and very humid air masses are found in the Tyrrhenian Sea. Patches of high CAPE are found in the forecast maps, but most of the storms are expected offshore. But even if the initiation happens over the sea, the strong westerly flow can bring them to the coasts of Italy. Downpours and severe winds will be the main threats.
.... Albania, Greece and Turkey ....
As the near-surface cold front crosses the Adriatic Ionian Seas, several storms are expected in the western coasts of the Balkans. CAPE and shear are maximised in the coasts of Albania and W Greece first, and later in the Aegean Sea. High accumulations of rainfall are expected in western Balkans, while in the coasts of Aegean Sea severe winds will be the main threat.
In S Turkey and N Cyprus, ongoing storm activity will continue on Tue 2/11 as short-wave trough is traversing northeast towards Middle East and provides lift to unstable air masses.A few supercells cannot be ruled out into this strongly sheared environment.
