Internet usage pattern during power outage in Spain and Portugal

Summary

A look back at the Iberian power outage of April 28 By Philip Tellis on 03 May 2025 Table of Contents On Monday this week, the Iberian Peninsula suffered a major power outage that disabled many services across these countries. In this post I'll look at the patterns we saw in mPulse data during this time. Overall traffic I first looked at the overall data patterns for traffic originating from Spain & Portugal for several weeks prior to the outage. While other regions were also slightly affected, these two countries suffered the worst of it. The image above shows traffic patterns for these two countries for 7 days around the event at 1 hour granularity. We see that on average (in that mode I mean the medians), Spain has about 4.5 times the traffic of Portugal. This is expected, since Spain's population (48m) is 4.5 times that of Portugal (10.5). Identifying the Anomaly I then ran mPulse's Anomaly Detection against this data. The Anomaly Detection logic shows that traffic dropped below expected levels between 12pm & 1pm CEST (local time in Madrid), and then returned to normal sometime around 2am on the 29th. This chart only shows traffic from Spain, but you get the picture. Drilling into the details I then looked at the data at finer granularity. This time at 5 minute intervals comparing April 28th to the week prior. Ideally I'd have used the previous Monday, but as that was the Easter Monday holiday, the traffic patterns were unusual on that day as well. I settled on Wednesday, April 23rd as a representative day for the prior week. Just to be sure, I also looked at data from France & Germany to make sure we weren't seeing a common change in pattern. Also, to be clear, for any of the following charts that refer to a single country, the time axis will be in that country's time zone. This means that Portugal shows up in WEST rather than CEST. The outage started at 11:33am in Portugal which is 12:33pm in Spain. I looked at several different dimensions, but the first one t...