Storm Forecast
Valid: Thu 18 Jul 2024 06:00 to Fri 19 Jul 2024 06:00 UTC
Issued: Wed 17 Jul 2024 15:34
Forecaster: TUSCHY

A level 1 was issued for far S-Turkey mainly for hail and severe downbursts.

A level 1 was issued for NE Turkey mainly for heavy rain.

A level 1 was issued for parts of SE/E Europe mainly for hail, heavy rain and strong to severe gusts.

SYNOPSIS

Most of Europe experiences blocking conditions with positive geopotential height anomalies. The main axis from an intense subtropical ridge runs from the SW Mediterranean area into the Ukraine.
A stationary vortex over the far S Gulf of Bothnia drifts E into S Finland and sparks ongoing bands of convection with heavy rain.
An upper trough is situated over Turkey and remains in place during this forecast period.

An eastbound moving cold front shifts into Belarus/Ukraine with EZ tracker loosing its identity somewhere in this region. Latest front analysis from DWD brings the front into the central parts of the Ukraine until 00Z (19th).

DISCUSSION

... Romania into Belarus ...

The prefrontal airmass features BL moisture content in the 12-14 g/kg range with meager mid-level lapse rates. Strong diurnal heating pushes MUCAPE in the 1000-2000 J/kg range with weak deep layer shear of 5-10 m/s due to relaxed height gradients.

Expect ongoing clusters from the previous night with a temporal weakening trend before noon, before re-intensifying during the day. Also, orographic convection is forecast, which could grow into disorganized clusters during the day.

The main risk will be hail, isolated large one, with initiating storms next to a few severe downburst events. Betimes with growing clusters, heavy rain and strong to isolated severe gusts are forecast with a lowered hail threat. An isolated tornado is possible along the boundary, where LCLs stay rather low. A broad level 1 area should cover this risk.

... Parts of Finland and Sweden ...

A marginal level 1 could have been added for a few heavy rainfall events within ongoing banded precipitation next to the vortex, where 500-1000 J/kg MUCAPE exists. NWP QPF maxima are widely distributed so confidence in placement was to low for adding one.

Peripheral of the background vortex, only marginal heating is needed for some better LLCAPE build-up and a few funnels/short lived tornadoes are possible from CNTRL Sweden into SW/CNTRL Finland. The risk is too low for any upgrade.

... Turkey ...

Ongoing marine heat wave with strong diurnal heating push a very moist sea breeze driven marine layer inland along the coast with numerous afternoon storms along the orography taking profit of 1000-2000 J/kg MUCAPE with weak shear. Slow moving and high-based storms (LFC aoa 2.5km AGL) bring hail and a few severe downburst events.
Along the Canik Escarpment along the S Black Sea, a weak LL vortex assists in agile CI with lots of offshore and coastal convection. Clustering storms bring locally heavy rain.