Temperature observed ...
The map says temp. observed 28 C in Larissa airport (LGLR)
METAR says 33C !
The problem happens because you use SYNOP (3 hourly) data
from airports wx. station (16648) instead of METAR (half hourly) data.
LGLR is colocated with 16648 meteo. station.
... in general I realize that all airports data are stuck at 07:00 UTC