Yesterday’s rain was pretty noteworthy. I got 0.93″ at my CoCoRaHS gauge. That would make yesterday the 3rd rainiest May day of the last 50 years here in Davis. It also instantly jumps us to being the 10th rainiest month of May over the last 50 years. With more rain predicted today and next week, this could easily end up being one of the top 5 rainiest Mays ever.
Below is a bar graph showing the sorted daily rainfall totals for May days over the last 50 years. Notice a few things: 1) the logarithmic axes, 2) X-axis values start at day 1412 because 1411 of May days over the last 50 years have seen 0″, 3) the values nicely fall along a line in the log-log plot (except for the very heaviest days). This last point is an example of ubiquitous “power-law scaling” in the Earth system in which intense occurrences are very, very rare but also very much more intense than common events (think something like the great San Francisco Earthquake compared to the weak shaking SF feels commonly). Yesterday’s rainfall didn’t amount to the quake of 1906…more like the Earthquake of 1989.