u500, v500 = u/v component of wind at 500hPa
u900, v900 = u/v component of wind at 900hPa
urgd10m, vgrd10m = u/v component of wind 10m above ground

'define dls = mag(abs(u500-ugrd10m),abs(v500-vgrd10m))'
'define lls = mag(abs(u900-ugrd10m),abs(v900-vgrd10m))'