Storm Forecast
Valid: Tue 28 May 2024 06:00 to Wed 29 May 2024 06:00 UTC
Issued: Mon 27 May 2024 20:29
Forecaster: TUSCHY
A level 1 was issued across parts of Turkey mainly for isolated large hail/severe wind gusts, heavy rain and a tornado or two.
A level 1 was issued for parts of SW Sweden mainly for isolated large hail/severe wind gusts, heavy rain and a tornado or two.
A level 1 was issued for NE Germany into NW Poland mainly for isolated large hail and heavy rain.
A level 1 was issued for parts of CNTRL Poland mainly for heavy rain, isolated large hail and strong to severe gusts.
A level 1 was issued E of Estonia/Latvia mainly for a few hail/gust events.
A level 1 was issued across parts of Bosnia and Herzegovina into Croatia mainly for isolated large hail/severe wind gusts and heavy rain. An isolated tornado event is possible.
SYNOPSIS
Not much change synoptic-wise with ongoing blocking over far W-Russia and a persistent subtropical ridge over Portugal/Spain. In-between, a channel with lowered geopotential heights extends from Iceland to the Black Sea and then further S into Egypt. Numerous vorticity maxima exist with enhanced curvature vortcity over Ireland/Scotland, Benelux into Denmark, Bulgaria into Romania and over the E-Mediterranean. Weak height gradients keep mid/upper flow on the modest side.
DISCUSSION
... Lightning areas and level 1 areas ...
Main focus for scattered to widespread CI occurs along/ahead of a leisurely eastward moving cold front over CNTRL Europe with modest MUCAPE in the 400-800 J/kg range (locally up to 1 kJ/kg) and weak DLS (in the 3-10 m/s range). Diurnal driven convection is forecast with upscale growth into numerous disorganized clusters. Heavy rain, isolated hail and gusty winds will be the main hazard.
A local level 1 upgrade was performed from Bosnia and Herzegovina into Croatia as MUCAPE in excess of 1 kJ/kg supports healthy updrafts with hail/gust and heavy rain issues. Robust 0-3 km CAPE assists in a few funnel/tornado reports. Rapid clustering is forecast.
A level 1 upgrade was performed over NE Germany with ID2 input showing some signals for a few better organized storms before noon with better 0-3 km shear. Timing of cold front passage defines this risk as other models already show the front more to the E.
A level 1 upgrade was performed over parts of Poland to reflect the somewhat more dynamic background over NW Poland with a few better organized storms but also the prefrontal N-S aligned convergence zone with decent CAPE of up to 1.5 kJ/kg MUCAPE and inverted-V profiles. Strong cold pools should limit heavy rain risk although colliding storms/clusters may support a few events. A few hail and strong wind gust reports are also forcast.
A level 1 upgrade was performed over SW Sweden ahead of the N-ward lifting Danish vortex with favorable kinematic/thermodynamic conditions for organized thunderstorms including a few supercells. Forecast hodographs with plenty of 0-3 km streamwise helicity indicate an augmented chance for rotating updrafts as convection initiates/stays discrete for some time. A tornado or two, large hail and severe wind gusts are possible with 15-20 m/s 0-3 km shear and a few IFS driven models even show a borderline level 2 setup between Malmoe and Goeteborg with a few longer-lived supercells. Collapsing SR flow above 6 km AGL and deep humid profiles with more widespread CI should support consolidating cold pools with upscale growth into a N-ward moving cluster with hail and a few severe wind gusts next to heavy rain.
A level 1 upgrade was performed just E of Estonia/Latvia for a few hail/severe downburst events with up to 1.5 kJ/kg MUCAPE and a well mixed BL. Coverage of storms is a bit uncertain with anticyclonic background flow but NWP guidance agrees in adequate CI for a local upgrade.
A level 1 upgrade was performed over parts of Turkey mainly for numerous multicell/isolated supercell events with all kind of hazards on an isolated scale. Pre-convective soundings and hodogrpahs indicate adequate shear (DLS in excess of 15 m/s) and CAPE (> 1kJ/kg MUCAPE) for large hail/severe wind gust and heavy rain issues. An isolated tornado event is possible with regionally lowered LCLs. Upscale growing convection shifts NE betimes.
A few high-based storms are possible over E Algeria with a severe downburst event possible, but marginal CAPE should limit updraft strength and storm longevity.
