Mesoscale Discussion
Valid: Wed 15 Oct 2025 18:00 to Wed 15 Oct 2025 22:00 UTC
Issued: Wed 15 Oct 2025 18:19
Forecaster: TUSCHY

This Mesoscale Discussion (MD) was issued to update the evolving severe risk for parts of the CNTRL Mediterranean area.

Since we now move more into the diurnal favored time-frame for new DMC activity, we monitor an area atop the SE Tyrrhenian Sea for a gradually structuring (but still ill defined) LL vortex. There are no verifications yet but the 12Z NWP suite finally points to the chance for a transient shallow warm core vortex with augmented gusts confined to the vortex' proximity. However we also see repeated CI of deep convection along the approximated S fringe of the potential vortex but we have to see if remote sense data verify anything closed later-on. Overall there is an enhanced risk for a confined area wit gale-forced winds atop the SE Tyrrhenan Sea tonight, probably not well captured in NWP data. Any spin-up would also be accompanied by excessive rain, probably also mainly offshore.

The southern MD was added to once again point to a confined area with back-building convection and extreme NWP rainfall amounts during the following 6-12h (numerous local model peaks in excess of 400 l/qm/12h). These clusters have to be monitored closely if they manage to build near the coastal areas, which would result in an excessive rainfall/isolated tornado risk. In addition this evolving cluster could also induce a transient LL vortex, which would result in hazardous marine conditions.

To summrize, marine conditions in the MD areas could become nasty on a regional scale, which probably is not well captured by model data. Surrounding coasts need to monitor this scenario, too, in case any vortex verifies and approaches the cost.

Outside of the MDs, the level 2 risk continues with excessive rain on a local scale the main hazard (next to a coastal gust/tornado risk).