Keep in mind that the advforecast2.php script (V5.x) uses api.weather.gov for data. The forecast.weather.gov site does not.. it uses the current production system. They are still refining/massaging/updating the API and sometimes, data gets lost/stale between the current production system and the API .. that's when you see the message and a failover to the Zone forecast in the advforecast2.php script.
If the outage is shown more than a few hours, I'd suggest calling the WFO listed and let them know.. they can get the GFS data reloaded to the API usually.
