Storm Forecast
Valid: Wed 10 Feb 2021 06:00 to Thu 11 Feb 2021 06:00 UTC
Issued: Tue 09 Feb 2021 23:38
Forecaster: PUCIK

A level 1 was issued across coastlines of the Central Mediterranean mainly for heavy rainfall, severe wind gusts, marginally large hail and to the lesser extent for tornadoes.

A level 1 was issued across southern Turkey mainly for marginally large hail and heavy rainfall.

SYNOPSIS

An active weather pattern remains along and to the south of a pronounced frontal boundary running across central Europe. To the north of the boundary, dry and cold continental airmass will offer environment too hostile for convective storms. Chances for convection will be higher south of the boundary, especially over the Mediterranean Sea where modest lower tropospheric moisture remains.

The most important synoptic-scale player at the mid-troposphere will be a pronounced trough over northern Iberia moving towards the Alps and the central Mediterranean and then amplifying over the Ionian Sea. Strong mid to upper tropospheric flow is simulated on its flanks. Another trough will move across southern Turkey during the day. At the same time, a ridge will move from the Atlantic towards Iberia and W France. Together with the strengthening of a surface high over Scandinavia, an outbreak of arctic airmass will begin in the overnight hours over parts of central Europe.

DISCUSSION

... Central Mediterranean ...

Much of the thunderstorm activity is forecast to occur on the forward flank of the advancing trough and ahead of an ill-defined cold front. Models agree on several hundreds J/kg of MLCAPE building over the coastlines thanks to the modest boundary-layer moisture and steep lapse rates of over 7 K/km. Ahead of the trough, strong vertical wind shear is forecast with rather straight hodographs, suggesting potential for splitting supercells. Stronger storms will be capable of severe wind gusts and marginally large hail. Low level shear can locally exceed 10 m/s, suggesting enhanced potential of tornadoes, but this threat may be diminished by the lack of hodograph curvature and thus lack of streamwise vorticity in the inflow to the storms. Heavy rainfall threat will be present especially over the western Balkans.


... Southern Turkey ...

In conjunction with the passage of the trough, scattered storms are forecast, developing in 0-6 km shear around 20 m/s and MLCAPE of up to 500 J/kg. Few of the cells may become supercells capable of marginally large hail and perhaps a short period of heavy rainfall.