Storm Forecast
Valid: Sun 05 May 2024 06:00 to Mon 06 May 2024 06:00 UTC
Issued: Sat 04 May 2024 22:26
Forecaster: PUCIK
A level 1 was issued across Iberia mainly for severe wind gusts and to the lesser degree for tornadoes or heavy rainfall.
A level 1 was issued across France to W Switzerland mainly for large hail and heavy rainfall and to the lesser degree for severe wind gusts or tornadoes.
A level 1 was issued from central Czechia through Poland into Lithuania mainly for large hail and heavy rainfall and to the lesser degree for severe wind gusts.
A level 1 was issued across Romania for heavy rainfall.
A level 1 was issued across the E Mediterranean, E Black Sea and SW Caucasus mainly for heavy rainfall and to the lesser degree for large hail.
A level 2 was issued across SE Turkey, N Iraq and Azerbaijan mainly for large hail and severe wind gusts.
DISCUSSION
... Iberia ...
A pronounced trough is forecast to cross the region. However, the mid-tropospheric lapse rates will be very poor, locally even below 6K/km. Therefore, rather low-topped storms scattered to widespread storms are forecast to develop in skinny CAPE profiles with little buoyancy below -10 deg C, virtually elimitating threat of large hail with an exception of SW Pyrenees. Given straight hodographs and strong mean flow, primary hazard will be severe wind gusts. Bulk shear around 10 m/s in the 0-1 km layer and local variation in the hodograph curvature may yield an isolated tornado threat. A heavy rainfall event is not ruled out either given that multiple storms are possible over a single area.
... France to extreme NW Switzerland ...
A weak cold front is forecast to cross the area, initiating scattered storms in the afternoon to evening hours. MLCAPE between 500 and 1200 J/kg is forecast with modest low-level moisture and lapse rates around 6.5 K/km. Forecast hodographs suggest well-organised multicells and supercells with 0-6 km bulk shear approaching 20 m/s. Slightly more curved hodographs with more low-level shear are forecast around the N fringe of the Lvl 1 and tongue of CAPE. Primary hazard will be large hail in supercells. While very large hail is also not ruled out, its likelihood is much lower given rather limited CAPE. Around N-edge of the Lvl 1, supercells may also produce a tornado with 0-1 km bulk shear around 10 m/s. Towards the late evening, eventual upscale growth may result in an enhancement of severe wind and heavy rainfall threat.
... Central Czechia through W/Central Poland to S Lithuania ...
A belt of CAPE between 500 and 1500 J/kg is forecast to develop across the area with mid-tropospheric lapse rates between 6.5 and 7 K/km, increasing towards NE. Forecast profiles reveal tall CAPE profiles with substantial fraction of buoyancy below -10 deg C. Hodographs suggest some well-organised multicells given the 0-6 km bulk shear mostly up to 15 m/s. Large hail will be the primary threat with the highest coverage of severe expected over N Poland. Heavy rainfall is possible given potential upscale growth in later stages in the evening. Should any storm develop in the afternoon hours over E Poland, it will also bear risk of downbursts given the Inverted-V profiles.
... Syria through E Turkey and N Iraq to Azerbaijan ...
A deep trough will move across the region with a synoptic-scale lift at its forward flank. Strong mid-tropospheric flow is forecast to overspread the area. Steep lapse rates and modest low-level moisture will result in 500 to 1500 J/kg of MLCAPE. CAPE will increase towards the E/SE with increase in the lapse rates, which will reach around 8 K/km over Iraq. Storms will be initiated by orography and by cold front residing over the region.
Across the Mediterranean and the adjacent coastlines, as well as over the eastern coastline of the Black Sea, the main threat will be excessive rainfall. Here, closer to the core of the trough, the storms are forecast to move slower. Hail and wind risk will increase towards E and SE, where forecast hodographs suggest supercells as primary convective type and higher LCLs are also anticipated. The risk of severe wind gusts will increase towards Iraq and Iran, where inverted-V profiles are simulated in deep boundary layer. The highest risk of large and perhaps even very large hail is forecast south of Caucasus, over Azerbaijan, where elevated supercells are forecast with abundant CAPE below -10 deg C.
... Romania ...
Basically stationary storms are forecast over the area with threat of heavy rainfall.
