Storm Forecast
Valid: Tue 23 Jun 2026 06:00 to Wed 24 Jun 2026 06:00 UTC
Issued: Mon 22 Jun 2026 09:55
Forecaster: TUSCHY
A level 1 was issued across parts of Romania into Bulgaria mainly for heavy rain, hail and gusts on a local scale.
A level 1 was issued for parts of SW Italy (Campania, Basilicata) mainly for heavy rain, hail and gusts on a local scale.
A level 1 was issued for the S Alps mainly for heavy rain, hail and gusts on a local scale.
A level 1 was issued for E Turkey into Georgia and Armenia mainly for hail, gusts and heavy rain. An isolated tornado event is not ruled out.
SYNOPSIS
An blocking warm-core anticyclone over W Europe keeps going. This ridge is filled with a tropical airmass, characterized by extremely low PV values, which advect northward (near zero PV along the 320K isentrope). An impressive atmospheric river with TPW anomalies in excess of 200% to the background climatology still points towards NW Europe and assists in that extensive pool of enhanced moist static energy, which further intensifies the northern part of the anticyclone by negative PV advection. An extremely hot airmass with H85 temperature anomalies in excess of 10-15K spreads further NW into NW Europe with a gradual cooling trend further E towards E Europe.
A stalling upper trough is foreacst W of Portugal with another trough over Turkey, which shifts E during the day.
A gradually dissolving cold front over SE Europe remains the focus for active CI with otherwise no synoptic-scale fronts forecast to drive any DMC risk.
DISCUSSION
... E Turkey into Georgia and Armenia ...
A strong but gradually filling upper trough crosses Turkey E with MSLP response over N Iraq/NW Iran and SE Turkey. This structuring surface low creates a corridor with backed winds along its N fringe, which affects most of the level 1 area beneath a strong subtropical jet from the SW.
Placed along the northern fringes of a pronounced EML atop seasonable BL moisture assists in modest MUCAPE build-up with local peaks up to 1500 J/kg. Enhanced shear at mid/upper levels assists in organized DMC activity and forecast hodographs reveal substantial curvature with lots of non-effective SRH. The main issue will be a warm sub H7 layer, which increases capping issues. Nevertheless, multicells and a few supercells are forecast in this forced convective regime downstream of the approaching trough with large hail, strong to severe gusts and local flash flooding. A tornado event is not ruled out with variable LCL heights in this complex orography.
... Romania to Bulgaria ...
Another round of diurnal driven intense pulsating convection (MUCAPE up to 2000 J/kg) is forecast with isolated hail, gusts and heavy rain
... N Italy ...
Scattered thunderstorms evolve along the orography from noon onwards, before drifting towards the lowlands, where CIN increases. A temporal severe risk is possible with hail, gusts and heavy rain.
... SW Italy ...
MUCAPE in excess of 3000 J/kg is forecast, so a few intense updrafts are possible with diurnal onshore flow towards the orography. Isolated hail, gusts and heavy rain is forecast.
... S-UK ...
A loaded gun pattern exists beneath the northward building ridge.
Anomalous high BL moisture content with mixing ratios up to 14 g/kg beneath a northward spreading EML support MUCAPE in excess of 2500-3000 J/kg. A hot airmass within the lower troposphere causes capped conditions for most of the day. A very weak wave passes E during the day, but seems too weak for any CI. The fringes of that CAPE plume need to be monitored for isolated CI (as CIN decreases) and the same for the coastal areas with some sea breeze activity. However neither EPS nor deterministic data show convincing support for CI. Hence only a low confident low prob. lightning area was added for now.
If CI becomes more likely, an update would be needed to reflect a large hail and severe downburst risk next to locally heavy rain.
During the start of the forecast, a low chance for lingering convection over SE UK is possible with a departing IPV lobe towards the SE, but confidence remains too low for a lightning area.
