Mesoscale Discussion
Valid: Mon 06 Oct 2025 10:00 to Mon 06 Oct 2025 14:00 UTC
Issued: Mon 06 Oct 2025 09:29
Forecaster: TUSCHY

This Mesoscale Discussion was issued to update the forecast severe risk. Please keep in mind that the MD's validity does not match the time-frame for the anticipated severe risk.

S-CNTRL Aegean Sea to W Turkey for the evening into the overnight hours:

Latest remote sensing data confirms organized nature of offshore convection, currently (09Z) approaching the coastal areas of far SW Greece with backed surface flow ahead.

As MSLP lowers atop the N Aegean Sea during the afternoon, a confined corridor with favorable CAPE/shear evolves along its S/SE fringe and will be highlighted by this MD. Constant increase of the BL flow into the structuring depression creates a sharp low-tropospheric convergence zone within this MD.

First expect organized multicells/isolated supercells to cross the MD E/NE with a gust/heavy rain, some hail and isolated tornado risk during the afternoon.

Of more concern becomes the effective influx of humid air into clustering convection during the evening into the overnight hours N of Izmir. Then, 0-3 km flow also increases from the W, so we could see a back-building MCS event with excessive rain. Dependant on where the training segment sets up, a regional but serious flash flood risk could materialize with forecast 150-250 l/qm during the overnight hours.
No changes to the SOWDY1 level areas for this MD.

Far NE Aegean Sea during the afternoon into the overnight hours:

This MD was added to nudge the level 2 a bit more to the NW to account for temporarily training convection with excessive rain. The high QPF peak more inland is related to non-thundery convection.

Far SE Bulgaria during the night:

There are still mixed signals regarding another nocturnal heavy to excessive rain risk for this MD. As MSLP lowers atop the N Aegean Sea, BL mass/wind response causes E/NE-erly onshore flow into the issued level 2 area. However it remains unclear, where any back-building convection can evolve as some models develop N-erly offshore flow along the coastal areas of SE Bulgaria, which would induce training convection mostly offshore. However not much push from the E is needed to take this effective convergence zone next to the coast. We keep this level 2, expand it a tad N and highlight an augmented risk for heavy to locally excessive rainfall amounts. This risk continues beyond 06Z and builds N.