The answer to your question:
no, you can't. There are many reasons for that.
Let me suppose that there is an event on server side, comming from the windows service, and you want all or some active clients to react to that (for example by sending some data not yet sent to the server side). The windows service will never be able to access the client. Neither can the web application hosted under iis. But your client can poll the web application for that specific event, which can poll the windows service using some IPC. Actually you could expose the windows service also, but I don't recommend that.
As an alternative
SignalR[
^] is a great tool you can use, but you still need to think about the client as the initiator of that communication.