Storm Forecast
Valid: Wed 08 Oct 2025 06:00 to Thu 09 Oct 2025 06:00 UTC
Issued: Tue 07 Oct 2025 15:18
Forecaster: TUSCHY
A level 2 was issued for E Romania for excessive rain.
A level 1 surrounds the level 2 for similar hazards with lowered probabilities. In addition, coastal areas could see an isolated tornado and gust event.
A level 1 was issued for S Turkey mainly for heavy rain, isolated gusts and a tornado or two.
SYNOPSIS
The unseasonably strong upper trough (temporarily trying to transform into a cut-off) over SE Europe remains the main driver for organized DMC activity. This trough and attendant surface vortex is about to lift NE towards the Black Sea.
In the meantime, thickness decreases over SW Europe in response to an arriving low-amplitude wave, which intensifies into a more zonally aligned upper trough over the Iberian Peninsula and the far W Mediterranean.
Brisk westerlies affect the W/N coasts of Norway and could spark a few short-lived thunderstorms with otherwise quiescent conditions beneath ridging over the rest of Europe.
DISCUSSION
Update from SWODY2 to SWODY1:
Not much changes were needed with similar level 2 and 1 coverage.
E-Romania experiences an ongoing and initially electrified heavy rain event with back-building convection along the coasts. Betimes, winds back to NE-erlies, which decreases the training risk. However more rain with the back-bent front is forecast and coastal areas could see an additional 100-150 l/qm in 12h.
No major changes for the level 1 over S-Turkey. A peak in QPF amounts is still forecast SE of Antalya, where a mix of coastal convergence zone and upslope flow along the orography induce rainfall peaks in excess of 100 l/qm/24h. If the coastal convergence zone evolves next to the coast, flash flooding is possible with augmented training probs. between noon and midnight. Opted to upgrade to a level 2 but modest inflow towards the convergence zone and moderate CAPE precluded an upgrade for now. Elsewhere a few better organized onshore moving thunderstorms bring some gusts, heavy rain and an isolated tornado risk to a broad area.
Also no changes for Spain, where mostly sub-severe convection is forecast until 06Z.
See the following discussion from SWODY2 for more informations.
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... E Romania ..
Dependant on how focused the deformation band affects E Romania, we could start to see serious flooding issues from this ongoing heavy/excessive rain event. Onshore pointing confluent low/mid-tropospheric winds advect unstable and humid air onshore into an ongoing and back-building MCS. Some guidance points to a another confined swath with 100-250 l/qm rainfall amounts in less than 12h for parts of the level 2. If this verifies we could see a rather extensive area with more than 200 l/qm in 48h, which would mean a serious (flash) flood threat (e.g. for Constanta). However that far out the uncertainties remain high, where the MCS could evolve and become quasi-stationary. EPS and deterministic data however give adequate confidence in such a scenario to issue another level 2 for this area. Coastal and surface based activity can also produce gusty winds and a tornado or two. This event should weaken until the evening hours.
... S-Turkey ...
A general/coastal level 1 was issued to highlight an ongoing local flash flood risk (especially around and SE of Antalya) but also an isolated gust/heavy rain and tornado risk with onshore moving convection in a modest CAPE and strong shear setup.
... Spain and offshore areas ...
A general uptick of onshore and later-on also offshore convection is anticipated beneath lowering thickness. Overall no serious severe risk is yet forecast but clustering convection could bring isolated small hail, heavy rain and gusty winds. We monitor this area for a potential/regional upgrade later-on.
