Weather Geekery: Seven Impossible Storms Before Sunset, etc.

One of the wonderful things about storms in an otherwise tranquil climate is it nicely demonstrates the meaninglessness of the Gaussian distribution with respect to modeling "normalcy". Check the following recent figure summarizing water discharge data from the San Diego river for an example:

impossible-weather

Based on 26 years of data for December 17th river discharge, today’s 1,260 cubic-feet-per-second flow value isn’t happening. It is out somewhere in the 99.99999th percentile or so. To a Gaussian "normality" way of thinking, we should see something like roughly on par with the surprise return of the Paleozoic era. Hey, maybe we’ll see a few subprime credit market analysts grab hands and leap into the river to prove this isn’t so.

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As a semi-related aside, you can’t get anything past the U.S. Forest Service. It has revised down the current southern California forest fire warning level:

The U.S. Forest Service, noting that most of the local mountains are buried under snow, lowered the official fire danger two notches today. More than 25 inches of snow have fallen on the highest elevations of the San Gabriel Valley…

Nothing like being buried in snow to reduce the chances of things catching fire.

Related posts:

  1. Weather Geekery: Neapolitan Ice Cream Weather in California
  2. The Trouble with “Impossible” in Complex Systems
  3. Weather: Storms Approaching
  4. Vancouver at Sunset
  5. Sunset in SoCal