edit the module node_helper.js

and change this code

        // console.log("[MMM-DarkSkyForecast] Getting data: " + url);
        request({url: url, method: "GET"}, function( error, response, body) {

          if(!error && response.statusCode == 200) {

            //Good response
            var resp = JSON.parse(body);
            resp.instanceId = payload.instanceId;
            self.sendSocketNotification("DARK_SKY_FORECAST_DATA", resp);

          } else {
            console.log( "[MMM-DarkSkyForecast] " + moment().format("D-MMM-YY HH:mm") + " ** ERROR ** " + error );
          }

        });

to look like this
(just copy/paste after selecting or deleting the old code above)

        // console.log("[MMM-DarkSkyForecast] Getting data: " + url);
        request({url: url, method: "GET"}, function( error, response, body) {

          if(!error){

            if(response.statusCode == 200) {

              //Good response
              var resp = JSON.parse(body);
              resp.instanceId = payload.instanceId;
              self.sendSocketNotification("DARK_SKY_FORECAST_DATA", resp);
            }
            else {
              console.log( "[MMM-DarkSkyForecast] " + moment().format("D-MMM-YY HH:mm") + " ** unexpected response code ** " + response.statusCode + " data="+body );
            }

          } else {
            console.log( "[MMM-DarkSkyForecast] " + moment().format("D-MMM-YY HH:mm") + " ** ERROR ** " + error );
          }

        });

then run mm again so we can see what the api is complaining about