Storm Forecast
Valid: Tue 25 Jul 2023 06:00 to Wed 26 Jul 2023 06:00 UTC
Issued: Tue 25 Jul 2023 06:23
Forecaster: PUCIK
A level 3 was issued across Slovenia, N Croatia, S Hungary and W Romania mainly for damaging wind gusts, very large hail and to the lesser extent for tornadoes.
A level 2 was issued across N Italy mainly for very large hail, severe wind gusts and tornadoes. A strong tornado threat will be present along the Apennines!
A level 2 was issued across N Hungary, E Slovakia, Ukraine and N Romania mainly for damaging wind gusts, large hail and excessive rainfall.
A level 1 was issued across Belarus and W Russia for tornadoes, severe wind gusts and to the lesser degree for large hail.
A level 1 was issued for E Latvia and Lithuania mainly for heavy rainfall and marginally large hail.
*** Severe weather outbreak continues with the threat shifting further east during the day! ***
DISCUSSION
... Slovenia, N Croatia, S Hungary, NW Romania ...
A band of intense storms has entered Slovenia from N Italy. The environment ahead is characterized by >1500 J/kg of MUCAPE combined with very strong effective shear. The storms will pose a risk of very large hail. Severe wind gusts are likely despite the fact that storms may be elevated at first. As the storms move E, daytime heating over Hungary may allow for the storms to become surface based. A development of bow echo is possible given 20+ m/s of 0-3 km shear. Extremely severe wind gusts threat will thus increase towards the later hours as the system moves towards Romania. Some forecast hodographs also show around 10 m/s of 0-1 km shear and large amounts of streamwise vorticity in the inflow to the storms. This threat will be conditional upon the convective mode and whether the surface heating will allow the cloud bases to become higher.
... N Italy ...
While the main line of storms has passed towards E, high-res models still indicate a development of more isolated storms, supercells, especially along the Apennines. Will maintain a Lvl 2. Shear profiles will remain extremely conducive for supercells capable of all hazards, but increasing dryness in mid-troposphere may inhibit the activity later on. A tornado risk will be present especially along the W flank of the Apennines, where models show 10+ m/s of 0-1 km bulk shear and 150 m2/s2 of 0-500 m SRH. If an isolated supercell moves across the region, a strong tornado risk can be expected in such an environment.
... N Hungary, Slovakia, Ukraine, ...
Widespread storms are forecast to form across the area in MLCAPE around 1000 J/kg (increasing towards S) and 15 - 20 m/s of 0-6 km bulk shear. Well organised storms are forecast to form, including supercells and large convective systems, that will move NE. Ukraine may be affected by a fast-moving convective system that will emerge from Ukraine. Expect multiple threats from storms, including large hail, severe wind gusts and heavy rainfall.
... Belarus to W Russia ...
ICON-EU shows large curve in the low-level hodograph, suggestive of a tornado threat over this region. Other models are more sceptical and the area needs to be monitored for the development of supercells. More marginal severe wind gust and large hail risk would be present besides this one.
... S Germany, Alps, SW Czechia ...
Ahead of the approaching short-wave trough, along the front, scattered to widespread storms are forecast to form, in the environment of MLCAPE up to 1000 J/kg and 0-6 km shear of around 15 m/s. Expect risks of large hail and isolated severe wind gusts from stronger storms, couple of which could be supercells.
... E Latvia and E Lithuania...
Forecast profiles show around 15 m/s of 0-6 km shear, allowing for at least well-organised multicells and brief supercells not being ruled out. In such scenario, marginally large hail may occur, which is otherwise limited by skinny CAPE and low LCLs. Heavy rainfall threat will be present in multicells, especially if multiple cells cross the same area, given high RH throughout the whole troposphere.
