Storm Forecast
Valid: Sun 25 Nov 2012 06:00 to Mon 26 Nov 2012 06:00 UTC
Issued: Sun 25 Nov 2012 07:33
Forecaster: VAN DER VELDE

SYNOPSIS

An intense depression lies over the North Sea and moves slowly to northern Denmark. The pressure gradients surrounding it are very tight and produces gale conditions from eastern England to western Denmark with the strongest winds north of the Netherlands. This depression currently is wrapping up its occlusion, surrounded by a WV dry slot. Its cold front is not well defined at low levels. The mid level cold front pushes into France and Germany. No deep convection is forecast around this low.
West of Ireland lies a satellite low with comma cloud appearance which is becoming the main low as the day progresses. Cold airmass at mid altitudes advects southward over the Celtic Sea. Cold convective cloud tops (EL<-20°C) allow some thunder, but CAPE is marginal along the occlusion, better in the cold airmass. By the end of the period instability is enhanced over the English Channel and storms may affect the UK south coast. An isolated severe gust or tornado is not ruled out, but the CAPE-shear overlap is not well established (in GFS model) and lacks veering with height. In some WRF models, SREH is locally around 200 m²/s² in the unstable air in the Channel.