At the risk of repeating myself…

…says the sky on August 5th, referring to almost the exact same sky as on August 4th at this time.  Also, both days had OCNL LTG (texting “occasional lightning” here in weatherspeak) off the to distant NE, unusual for this time of day.   Even heard thunder this AM.

Below, which shot is from today, just now, and which boring shot of “stratiform” debris clouds from complexes of Cumulonimbus clouds that have dissipated instead of arriving here full strength boo-hoo is from yesterday?

7:02 AM, August 4th.  Altocumulus castellanus deck with Altostratus cumulonimbogenitus (watch out how you pronounce this in mixed company).
6:07 AM, August 5th. Altocumulus floccus/castellanus deck with Altostratus cumulonimbogenitus (watch out how you pronounce this in mixed company).

 

7:00 AM, August 4th.  Altocumulus castellanus deck under Altostratus cumulonimbogenitus.
7:00 AM, August 4th. Altocumulus castellanus deck under Altostratus cumulonimbogenitus.

So what’s the routine now? Gradual thinning with isolated showers, ones that also eventually disappear, followed by brighter skies, and growing of Cumulus clouds like desert weeds in July after the first rain. You’ll have noticed by this time that was a cloud scruff (Stratus fractus) on Ms. Lemmon today, indicating that the moisture is enhanced today over yesterday when the bases were appreciably above Ms. Lemmon. So, a better chance of rain, sans any model glimpses, but then since rain was very sparse yesterday, except for that 2 inches that fell in the mountains S of TUS yesterday afternoon (1.61 inches measured at the Florida Canyon Work Center), almost anything would be an enhancement of a rain chance here over yesterday so I have fudged some words here.

What happened to produce all these dense, morning clouds the past two days? Cloud gigantism in northern Mexico last evening and overnight. Must have had a TON of precip in these complexes that just exploded down there, inches of rain no doubt fell. Sure wish we had some reports under these magnificent blow ups. There are quite a few rain measuring stations in Mexico, but that data is not available from remote areas until they’re published. Here’s a view of last night’s Mexican eruption from IPS Meteostar.

!! PM AST U of AZ mod has rain “on the mountain” (the Catalina ones)  by 3 PM AST, and, like yesterday strong storms to the south of us heading this way.  But, like yesterday afternoons showers down thataway, they don’t make it here, the model reports.  You can do the loop for precip here in their rendition of the WRF-GFS mod.  Hoping Mr. Leuthold, our U of AZ expert, will shed further light on this when he reports here today between 10 and 11 AM.  In the meantime, I am sure convection expert, Bob (Maddox), will have something to say before then.

Not looking that great for a juicy August rain season here in Catalina Sutherland Heights….  Recall last year we had about 8 inches in July and August here, and at the end of August the mountains and grasses were SO green!

The End.

 

 

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.