Geopotential Height, Isotachs and PVA at 300 hPa

9 Aug 2005/00 UTC - Meteosat 8 IR10.8; Geopotential Height 300 hPa (solid green), Isotachs (solid yellow),PVA (solid red).

The upper level trough approaches from the south with distinct PVA maximum ahead of it. PVA max is located at the left exit region of the Jet Streak. It is noteworthy to mention here that at 300 hPa we still can see a trough while at lower levels (see Synoptic Situation chapter) the trough had already turned into a closed low.