Thursdays

During breakfast today, BH observed, à propos of something or other, that Thursdays were the wettest day of the week. She knew, from her years of playground duty. Challenged, she talked of weekly cycles of pollution from motor traffic.

Curiosity aroused, I asked Bing, who turned up reference 1, reporting on some work in 2009 by one Andy Russell, then of the University of Manchester, work which included the claim that there was a weekly pattern to rainfall, with Tuesday being the wettest day. But I was unable to turn up any proper write-up of this work.

Turned to Google, who turned up what looked like a more serious report in Nature at reference 2. Where the story seems to be that there might be a weekly cycle but it would be weak and confused. Although there was some evidence of such a cycle emerging, in the US at least, over the last forty years.

However, I put my money on reference 3, the first reference in reference 2. In which we get the results of analysis of the rain records from over 200 weather stations in the US, also covering more than forty years. They say no pattern.

But clearly a topic which is both interesting and newsworthy, a topic which will be kicked around for a long time yet, occasionally resulting in loud headlines in the tabloid press (and their online equivalents).

Reference 1: https://www.manchester.ac.uk/discover/news/tuesday-wettest-day-of-week-suggests-new-analysis/.

Reference 2: https://www.nature.com/news/2007/071207/full/news.2007.345.html

Reference 3: Weekly precipitation cycles? Lack of evidence from United States surface stations - David M. Schultz, Santtu Mikkonen, Ari Laaksonen, Michael B. Richman - 2007. Open access.