30th May 2005: 0600UTC
In the image the lifted index is presented. This stability index is the output of the SAI product of the NWC SAF. A negative value indicates an unstable air mass, while a positive value implies a stable air mass. The value is color-coded with reds and yellows being the most unstable and blues and beiges more stable. At this stage the region over Central Europe where the convection at a later stage will start is still recognised as stable. Further south over the Mediterranean and also over the coast of Croatia more unstable regions are recognised.
30th May 2005: 0630UTC
30th May 2005: 0730UTC
Ahead of the front some small patches of blue are now recognised indicating negative values for the lifted index. This regions should be looked at in following timesteps as it is an indication for an unstable atmosphere.
30th May 2005: 0800UTC
30th May 2005: 0830UTC
30th May 2005: 0900UTC
30th May 2005: 0930UTC
A considerable increase was seen in pixels indicating negative lifted index values (also compare with 30 minutes before!). They mark the spots where in one hour the large convective event will start.