Rainfall - better statistics, update

Our recent rains topped us out at a seasonal total of just over 1" in my backyard. This is well below normal by any measure of normal. Following some back and forth between Grace and I, I've recast my previous rainfall statistics in terms of median and quartile distributions (maintaining the mean for comparison purposes with previous graphs). As Grace noted, the median is less than the mean indicating that we "typically" have fewer heavy rainfall years, among a greater number of years of lesser rainfall. The first and third monthly quartiles (the number having 25% and 75% probabilities, respectively, that rainfall is greater than it) are graphed here, along with the median, mean, cumulative mean and cumulative median measures of total rainfall. The area covered by blue "pool" texture is the monthly 50% probability that we'll have rainfall between its upper and lower limits. So for January (which by this measure is the second heaviest rainfall month) there is historically a 50% chance of rainfall between about 0.71" and 3.84".

In my backyard, this January's contribution to the seasonal total of just over 1" was only 0.315".

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