Storm Forecast
Valid: Mon 14 Oct 2013 06:00 to Tue 15 Oct 2013 06:00 UTC
Issued: Mon 14 Oct 2013 08:22
Forecaster: PUCIK

No threat levels have been issued.

SYNOPSIS

Quite complex synoptic setup has developed over Europe. A cut-off low will remain centered and rather quasi-stationary over England with another trough approaching Europe from the Atlantic and a ridge building between these two features. A trough from the low will strech all the way towards the southern Mediterranean. Strong zonal flow along with several disturbances are forecast over the northern half of Scandinavia and Russia. Closer to the surface, low pressure systems will cover NW / N sector of Europe with Central Europe remaining in a weak pressure field with a high pressure over Eastern Europe. No significant frontal boundary is forecast perhaps apart from the strong cold front pushing across Scandinavia towards the south.

DISCUSSION

... Central France ...

A weak WAA along with PVA is simulated over the region in a belt of 20 m/s flow around 500 hPa. Cold mid-level temperatures will contribute to the steeper lapse rates, so that some low-end latent instability is possible (up to 400 J/kg of MUCAPE). With deep layer wind shear reaching around 20 m/s and shear in the lowest 1 km around 10 m/s (especially towards the evening), it is possible that stronger updrafts could profit from the stronger shear and become well-organised. A marginal threat of severe wind gusts and/or tornadoes will exist over the region, but is very conditional due to the instability issues. Thus we refrain from issuing a Lvl 1 attm.

... Southern Italy ...

Steep mid-level lapse rates are forecast to advect over the region in strong southwesterly flow, creating a potent situation for strong and well-organised DMC with moderate latent instability and favourable vertical wind shear. However, most of the NWP does not count on with the initiation because of the enhanced CIN values.