When this was DarkSky, the service was solid. I don't ever remember an outage. Ever since Apple bought them it's been extremely unreliable. I regularly get random 5xx errors from them. This is the first time I know of that they've acknowledged an outage. According to their System Status (
https://developer.apple.com/system-status/) it's been down for almost 3 hours now.
Oddly, this other system status page: https://www.apple.com/support/systemstatus/ seems to think everything is OK. It's not really clear to me why they have different system status pages.