IMS Snow Cover products used to asses ECMWF snow cover (contingency table):
IMS snow cover maps
IMS snow cover time series
SYNOP two-metre temperature:
SYNOP T2m maps
SYNOP T2m time series
SYNOP two-metre relative humidity:
SYNOP RH2m maps
SYNOP RH2m time series
SYNOP snow depth
SYNOP snow depth maps