The storm door is closed

Or so says chuck b. over at My Back 40 (Feet). I've been thinking the same thing myself this whole last week, and particularly as I watered and weeded in my yard on Sunday. Oops - I think that I expected gloomier weather to give my lettuce a bigger break and it's wilted to the point of being unrecoverable.  The long term forecast agrees with us too - no rain 10 days out, which takes us nearly to the end of March. The chances of further rainfall go down dramatically in April and May.  So, at risk of being wrong (which has never stopped me before) I'll post some "final" rainfall statistics. Of course, it ain't over 'till the fat lady sings - some time in April or May is when we have our last (and low) expectation for rain this season. If we do get more rain, I'll have to post an update.

Contrary to seeming widespread perception, the overall assessment of this rainy season in the Los Angeles area is only "somewhat above average", assuming we have no more rain.  Maybe people are mentally comparing to the last few years, which have been on the lower side of rainfall (see the graph above).  However, this year, total rainfall in my backyard is 13.70" which doesn't qualify as exceptional.

Here's why: In nearby Los Angeles median rainfall is 10.24" and there is a 50% chance of having between 8.21 and 14.94 inches of annual rainfall*. There's a 25% chance of having less than 8.21" or more than 14.94".  These numbers are close to what I expect in my backyard.  Therefore, if we get no more rain this season, we'll end up in the big fat middle of the annual rainfall pack, somewhat above median (which is pleasing), but not enough to go down in any history book as remarkable.

17 Mar update
Bad Mom pointed out via email that there's a high pressure zone blocking incoming storm systems off the coast of northern California which you can visualize using sea level pressure maps located here, showing millibar of pressure.  She notes that 1032 mb (updated link shows 1034 mb) is quite high and comments on the Aleutian low to its west.

*I think I have reported different numbers before, but today I realized that I had a small error in my analysis. The important point is the same - that there's a wide span of typical annual rainfall.


  1. Wow! Is that all the rain we have gotten? That is amazing because it does seem like we had so much this year! I always explain to people that our average is 13" a year, but that really means we get 2" one year and 20" the next, rarely ever the actual average!

  2. It is really interesting to see what the figures are, as opposed to your perception. I'm in inland Nor Cal, so we get a bit more rain - sometimes.

    We got that storm last night, and it's still here...don't know if that affects you or not. One thing I like about weather: no one can tell it what to do.