Windows Azure is a global service. To ensure that applications behave the same way regardless of their physical location, it’s important that Windows Azure have a consistent time zone across all geographies. UTC is a natural choice given our global customer base, and UTC is not subject to Daylight Saving Time (and the associated risk of bugs).
Currently, the time zone within Windows Azure is Pacific Standard Time (PST). Soon, we’ll be migrating to Coordinated Universal Time (UTC). This is potentially a breaking change for applications which rely on local time.
If your application running in Windows Azure relies on local time, you will be impacted by the migration to UTC. Here are a few examples of potential issues:
Gaps may occur in event logs if local timestamps are used.
User interfaces that depend on local timestamps may show different results.
Local timestamps stored by your application may be interpreted differently after the changeover.
Many applications have already been designed to rely only on UTC time. These applications should be unaffected.