Bob Tisdale has published a book based on his insightful weblog posts, titled and available from
I have a copy of his book and recommend it. Even if you do not agree with some (or even all) of his findings, he has provided information as to how to access the original data in order to do your own analysis in Chapter 9 titled
Basic Instructions for Downloading Climate Data and Creating Graphs
We need more such competent scientific presentations where the authors present details as to how to access the raw data, in this case by using the KNMI Climate Explorer, as well as to complete analyses using that data such as Bob has done. I also encourage Bob to pursue submitting his work to peer-reviewed journals.