Cannot check/test right now but you might try out something like below, afaik I tested this in the (far) past and it worked if I remember correctly:
formatter: =v=>(v===0)?'':v+''
not sure what v+'' should do but just wanted to directly map your example (please note example above was not tested just pointing into direction you might try out).
Maybe if you share complete example it would be easier to check …
Just to mention I’m using Compass card to display wind direction and it’s css based, fyi.