go to radar.bourky.cz, select 8 pictures between 31.07. 12:45 and 14:30 UTC and watch area south of Brno (southeast corner of the Czech Republic, LKTB). pictures are just 15 minutes apart…
Impressive speed, to build from nothing.
However there were plenty of TSs in the vicinity so presumably the instability (a rapid lapse rate, plus humidity) was present just about everywhere.
Yes, the instability was present since morning, you can feel it for sure. So nothing surprising but stil..
