Enhanced meteogram

[meteo GR]

What is the continuous grey line in the cloud-rain section of ECMWF's meteogram?
Pressure diagram?

Pls have in mind that in the aviation community
usually such line represents
isotherm of 0 degrees Celsius (freezing level)
(like the white line in the airgram).

[meteo GR]

another look (giving ideas) Prague meteogram

[meteo GR]

Hmmm ! Snow in your area (Prague) next week ?
Lucky you !