Natural climate variability. They probably also live within the 100-150 year flood plain (or 50 year) and were just lucky to have avoided being innundated in the past. And more sources of runoff (streets, parking lots, etc) probably don't help matters.
It's being predicted that we are going to see a downturn in temperatures soon, somewhere to the tune of 1.5C by 2028 or something. This is because of solar cycling. It will be interesting to see if this pans out. Already, we are seeing temperatures on a decline from 1998. Of course, our temperature records are being rewriten every day through "filters" and there are a lot of scientists who refuse to release their data sets and methodologies for others to examine that are not within their circle.
So these "old, outdated" records that get referenced are some of the only raw and true data that exists.