Cloud joy; all kinds of ’em; next rain chances on the 21st and again on the 29th

A couple of Pima County gauges reported measurable rain yesterday or overnight, but that was about it. But it was a fabulous cloud day yesterday.  Heavier spotty rains, one USGS station indicating over an inch, fell in the central and northern mountains, which is good.

Below, a rehash of yesterday’s great variety of clouds.

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7:48 AM.   Altocumulus lenticularis clouds beyond the mountains to the SE of Catalina. Lenticular clouds indicate a stable layer of air, one resisting being pushed up, the opposite of what the slender Cu below indicated.  So, an usual sky for us yesterday morning.
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8 AM. Towering Cumulus atop Ms. Lemmon indicated how unstable the air was just above mountain top level. Underexposed for dramatic silouhette look. The smooth top on the right would be Stratocumulus lenticularis, again an odd juxtaposition.

 

10:37 AM.  Then you had your Altostratus mammatus/testicularis.
10:37 AM. Then you had your Altostratus mammatus/testicularis.
3:08 PM.  Your Cumulus mediocris topping the Catalinas with a few Altocumulus above; nice shadows and sun quilting.
3:08 PM. Your Cumulus mediocris topping the Catalinas with a few Altocumulus above; nice shadows and sun quilting.

 

 

3:09 PM.  And you had your "weak" Cumulonimbus capillatus clouds to the north.
3:09 PM. And you had your “weak” Cumulonimbus capillatus clouds to the north.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4:09 PM.  Dramatic scenes of banked up Stratocumulus over the Catalinas, Altocumulus top side.
4:19 PM. Here’s a better shot of the Altocumulus perlucidus (here) top side.

 

 

4:33 PM.  Nice example of glaciating smaller Cumulus remnant north over Saddlebrook.  Likely some sprinkles reached the ground under that ice plume.
4:33 PM. Nice example of glaciating smaller Cumulus remnant north over Saddlebrook. Likely some sprinkles reached the ground under that ice plume.  As you know, takes ice to get rain in AZ.
4:34 PM.  More sunlight and shadow drama due to Stratocumulus and Ac perlucidus above.  Was indoors socializing so didn't see sunset.  Hope it was a good one.
4:34 PM. More sunlight and shadow drama due to Stratocumulus and Ac perlucidus above. Was indoors socializing so didn’t see sunset. Hope it was a good one. I am beside myself thinking about how happy you were seeing all these kinds of clouds in one day!

 The weather ahead

Models beginning to act quite well now.  A little rain is foretold for Catalina and environs on the 21st of November, but Enviro Can make that storm look more significant and slower to move in, on the 22nd.  Still two mods, both having some precip?  Its all good.  First, for your viewing pleasure and because it portends more rain, from Canada, this:

Valid for 5 PM, November 21st.  Low and lots of rain shown banging into Cal.
Valid for 5 PM, November 21st. Low and lots of rain shown banging into Cal.  Would be here  about 24 h later, or on the 22nd.

 

Also valid for 5 PM AST, November 21st, this depiction of the flow at 500 mb.
Also valid for 5 PM AST, November 21st, this depiction of the flow at 500 mb.

 

An aside:   the Canadian model tends to have a westward bias, that is, a storm is foretold to be farther west a few days out than it turns out to be, something I’ve learned since becoming a forecaster yesterday (hahaha, just kidding,  if anyone’s reading this far).  So you have to figure the Enviro Can depiction of a trough off Frisco, Cal,  is really going to be inland that bit.  The US mod output shown above,  has this same trough going more overland before it gets to us than the Canadian one, and so there’s less cloud water in it by the time it gets here.  Root for the Canadian “solution”!

Farther down the road….more illusory water on the hot highway?

And, of course, a heavier rain is once again over Catalina and vicinity as November closes.  This model really likes Catalina and SE AZ!  Check it out:

Valid for 5 PM AST. November 29th.
Valid for 5 PM AST. November 29th.

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.