Storm Forecast
Valid: Wed 07 Nov 2012 06:00 to Thu 08 Nov 2012 06:00 UTC
Issued: Tue 06 Nov 2012 20:28
Forecaster: PUCIK

A level 1 was issued for SW Iberia, E Greece and SW Turkey mainly for excessive precipitation.

SYNOPSIS

A complex synoptic pattern will evolve with a deep, positively tilted trough pushing towards Eastern and Southeastern Europe. Subsequently, prevailing northwesterly flow will establish over most of Northern, Northwestern and Central Europe. A short-wave trough will affect British Isles during the evening hours and a cut-off low will be persistently hovering above the western coastline of Iberia. Closer to the surface, a deep low pressure system will cover the whole northern half of Europe while a ridge extending from Atlantic to Western Europe will amplify towards east with separate center developing over the Balkans.

Speaking of DMC ingredients, moisture starved environment will dominate Europe apart from SW Iberia and the Aegean Sea. Falling geopotentials and cooling mid-levels will promote some built up of latent instability over these regions and scattered DMC is quite plausible with favorable forcing.

DISCUSSION

... SW Iberia ...

On the forward flank of the stationary cut-off low, perpendicular low and mid-level flow to the coastline will be observed. A tongue of moister and slightly unstable airmass along with low level flow paralleling boundary point to the possible isolated event of prolonged, excessive precipitation albeit it is unlikely that extremely heavy rainfall would be observed due to the rather weak updrafts and insignificant moisture transport.

... E Greece, SW Turkey ...

As the sharp trough pushes across the region, pronounced PVA at its forward flank along with the exit region of the associated mid-level jet streak will contribute to the strong upward forcing and cyclogenesis over the Aegean Sea and Turkey. While the high pressure builds over the Northern Balkans, low level easterly to northeasterly flow will be likely, opposing the mid to upper level flow. Moreover, strong convergence signals are simulated by NWP over E Greece. Here, a long duration MCS could be an option and with dewpoints between 16 and 20°C in the area, it could easily pose a risk of excessive precipitation. SW Turkey will not see such a favorable setup but it is likely that higher low level moisture and CAPE values will be present here, so we included it into the risk.