An icy 0.06 inches Catalina dessert

Like most people, I like dessert, especially if its precip in the desert.  Yesterday’s “graupelly” fall of little ice ball showers weren’t expected, a surprise entree.  Even the local model run by the U of AZ weather department on their “Beowulf Cluster” of computers had the showers staying to the north.  So as a weatherperson, you would go with those models; “hey”, they’re the best we can do.  That’s what the TEEVEE weather guys do, too, unless they are really great and can tweak and improve them by knowing the kinds of errors the models make.

A side light:   A professor of weather at the University of Washington recently gave a big lecture about how it is useless for the National Weather Service to try and beat the computer models for tomorrow’s and beyond weather.  As in the humorous take on that old spoken word, how-to-live song, Desiderata,  “Deteriorata”, by the Fire Sign Theatre back in the 70s, this professor told the NWS to, “Give up”;  devote your time to getting the first day right, among other things.  The computers have a tough time in the first 6-12 h, as we saw yesterday.

Yesterday, you could see  the “errors” developing right off the bat.  All of the billions and billions and billions of calculations by the models, to say something Carl Sagan, the astronomer-cosmologist might say if he had been a weatherman, were unraveling; going wrong, incorrect, getting an “F” for rain/snow prediction.    It was going to be a bad day for the computers, who, as we know, generally know more than we do, especially about us and the things we do and buy.

Yesterday, the first exciting hint for me that the showers might reach here rather than just be a little to the north as the models said, was this scene whilst out with the dogs around first light, 7:30 AM.  Look at that shower going by the Charleau Gap!  I thought I might see lightning!  But then I usually think I am going to see more in weather, and in other areas of life, that I want to have happen than actually happens.  I thought, for example, that the Washington Huskies would beat the woeful Oregon State Beavers in football.   Actually fairly confident there.  But, “no”, it didn’t happen.

Back to weather:  the proper weather person would have exclaimed when seeing showers to the left and to the right early yesterday morning (and popping out on the TUS radar) as I did, “Wow”, these clouds have ice in’em!  And that wasn’t supposed to happen!”

So this was the first sign that we had a good chance of showers/snow yesterday.  It was a truly great moment because the computers are so often correct.

But yesterday, they were going down!  Cumulus congestus/weak Cumulonimbus clouds everywhere!

I felt great.  When weather computers fail on the dry side, it makes me feel better as a human.   And  of course, seeing these shafts of precip, you could opine knowledgeably to you friends that the cloud tops are likely colder than -10 C (4 F) (since ice formation in clouds before that temperature is reached would be unlikely here in AZ).

Here are some additional shots from that glorious day yesterday, including, for Oregon State fans (“hey”, the former company team is going to a bowl game!) a closeup of “graupel” for your viewing pleasure.  The last shot is when subsiding air arrived and squashed the Cumulus down over the beautiful Catalina Mountains into “humilis” versions late in the afternoon.

The weather ahead?  A strong storm still shows up in about a week.

The End, except for trying to get this layout right!

 

By Art Rangno

Retiree from a group specializing in airborne measurements of clouds and aerosols at the University of Washington (Cloud and Aerosol Research Group). The projects in which I participated were in many countries; from the Arctic to Brazil, from the Marshall Islands to South Africa.