Weather Conditions on May 27th, 2013
Wavy jetstream leading to a meridional circulation on Northern Hemisphere. Over and over troughs are detaching from jetstream, over Northeast America, over North Pacific Ocean and over Europe. Recently we have witnessed a wavy jetstream more and more frequently. A possible reason for it is increased warming in the Arctic relative to other regions of Earth caused by ice-albedo-feedback. Well, the jetstream is driven by gradient in temperature between Arctic and mid-latitudes. And this gradient is lessened by Arctic warming leading to a weaker more wavy jetstream.
The low pressure system in North Atlantic jetstream trough appears as a very nice! Cellular clouds indicate cool air following the low´s cold front. It goes like this: Cool air flows above warmer ocean’s surface – a labile air layering(!) – hence cellular convection cells come up within cloud formation starts. Also there is a cut-off low (a pool of cool air) over Eastern Europe inside one of the former trough detached from jetstream. Rainy weather in Central and Eastern Europe!
Jens Christian Heuer