module load cdo

cdo -f nc copy h14_2019053000_r.grib h14_2019053000.nc

cdo -sellonlatbox,5,19,36,48 h14_2019053000.nc h14_2019053000_Italy.nc

#Note that the size of the file is vastly reduced (h14_2019053000.nc ~ 25 mb, h14_2019053000_Italy.nc ~ 70 kb)!

for file in *.grib; do cdo -R remapcon,r1600x800 -setgridtype,regular "$file" "$file".reg; done #To convert to regular grid
for file in *.reg; do cdo -f nc copy "$file" "$file".nc; done #To convert regular grib files to netCDF 

for file in *.nc; do cdo -sellonlatbox,5,19,36,48 "$file" "$file"_italy; done #To extract Italian domain

cdo mergetime h27*.nc time_series.nc