We've confirmed that all systems are back to normal with no customer impact as of 6/13, 21:30 UTC. Our logs show the incident started on 6/13, 17:30 UTC and that during the 4 hours that it took to resolve the issue some customers in the West US region will experience a gap in data of up to 80% of ingested metrics.
Root Cause: The failure was due to a service scaling issue during deployment.
Incident Timeline: 4 Hours & 0 minutes - 6/13, 17:30 UTC through 6/13, 21:30 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.