Posted by Dr-Pete Yesterday morning, we woke up to a historically massive temperature spike on MozCast, after an unusually quiet weekend. The 10-day weather looked like this: That's 101.8°F, one of the hottest verified days on record, second only to a series of unconfirmed spikes in June of 2013. For reference, the first Penguin update clocked in at 93.1°. Unfortunately, trying to determine how the algorithm changed from looking at individual keywords (even thousands of them) is more art than science, and even the art is more often Ms. Johnson's Kindergarten class than Picasso. Sometimes, though, we catch a break and spot something. The First Clue: HTTPS When you watch enough SERPs, you start to realize that change is normal. So, the trick is to find the queries that changed a lot on the day in question but are historically quiet. Looking at a few of these, I noticed some apparent shake-ups in HTTP vs. HTTPS (secure) URLs. So, the question becomes: are these anecdotes, or do ...