Mar 3, 2015

Why winter rains matter most

South Florida has a reputation for summer rains,

But there are periodic winter deluges, too.

The historical calendar above shows the most recent Big Rain Day (BRD) relative to the historical record from 1992 to present. BRDs are shown as dark blue drops.  Middling Rain Days (MRDs) are shown as light blue dots.  Days with no appreciable rain in south Florida are indicated by an orange dot.  As you can see they are most frequent of the three, especially during the winter.

This weekend as case in point:

Saturday registered as an official Big Rain Day (BRD). A BRD is any day in which an average of one inch of rain falls across every square inch of south Florida over a 24 hour period. Saturday's Big Rain day marked our first since August 2014.


Winter BRDs aren't as rare as you might expect.

You have to go all the way back to the Winter of 2008-2009 to find a dry season one didn't fall. What's interesting is that I don't remember that as a very dry dry season unlike the deep drought Winter/Spring of 2011 that had two.

This bar chart shows the monthly distribution of BRDs from 1992 to 2013.  June has the highest proportion of BRDs and 

Goes to show that Middling Rain Days (MRDs) also count.

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