NCEP GFS half degree model

Param	-2	-1	today	+1	+2
icecsfc	-2	-1	today	+1	+2
icetksfc	-2	-1	today	+1	+2
snodsfc	-2	-1	today	+1	+2
pressfc	-2	-1	today	+1	+2