The cloud outage that should terrify the CIO

September 3 started like any other Thursday, until it didn’t. Within roughly 90 minutes, ChatGPT, Claude, Grok, and even Microsoft’s own Copilot were degraded or dark, knocked sideways by a failure in Microsoft Azure’s East US region . Downdetector logged more than 37,000 reports for ChatGPT alone, more than 1,300 for Claude, and roughly 1,365 for Grok.