I couldn't find the answer to this (perhaps I missed it): what is defined as an outlier?
"Armed with this refined dataset, we computed the historical range of low and high temperatures for each station for each month of the year. We then compared each station's daily temperatures to its corresponding monthly distribution. If one or both of these measurements fell in the bottom or top 2% on a given day, we labeled it an "anomaly" according to the typology above."
In case it wasn't apparent to you, there were a number of fairly obvious (let's call them "junior") errors of reasoning embedded in the original posting. As in, the kinds of things we would have readily lost points for in that undergraduate-level "quantitative reasoning" course we crammed through on the way to fulfilling our social science degree.
Wholly independent, mind you, of all the fancy-schmancy talk about generalized linear models and whatnot. Which, while being quite nice-sounding, serve only to distract from the more basic (and glaring) errors of inference in the surrounding text.
Which, in turn, is why the label "dataviz" is a more than appropriate description of the otherwise quite fun and entertaining HTML5 demo provided by the Enigma team.
"Data science", however, it is not.