Final Update: Tuesday, 24 September 2019 00:22 UTC
We've confirmed that all systems are back to normal with no customer impact as of 09/23, 22:30 UTC. Our logs show the incident started on 09/23, 21:30 UTC and that during the 1 hour it took to resolve the issue some customers using Application Insights in West US Region might have experienced intermittent data Latency,data access and data gaps for metric data and also might have experienced incorrect metric based alert activations.
Root Cause: The failure was due to issue with one of the dependent services.
Incident Timeline: 1 Hour - 09/23, 21:30 UTC through 09/23, 22:30 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.