Clouds disappointed yesterday

Clouds weren’t really what I expected yesterday, though they were exactly what the artificial brains of weather models with their millions-billions of calculations expected (no rain around).  So I don’t feel much like talking clouds today.  Perhaps they need a break.

Continuing anyway, I REALLY expected, with those early Altocumulus clouds and high dewpoints around these parts (high 50s in the morning), to see a nice Cumulonimbus on the Catalinas in the afternoon yesterday, along with a couple of rumbles, too.  Especially with -10 C at 500 mb (at about the level where those morning Altocumulus were located).  That’s an extremely low temperature for July at that level and suggests a lot of instability!

But it was about +10 C about 5 feet above that level–that is, there was a TREMENDOUS inversion just above that low temperature–you may have inferred that from all the flat, deeper Cumulus tops around, ones that tried to stick up into that inversion.  I’m exaggerating some here, but it was a very strong inversion that was present.  Also, the air was continuing to dry out during the day yesterday, not moisten up as the day went on until very late and I had not noticed that in the water vapor imagery since I didn’t look at it.  Bad meteorologist!

Check out the movie for yesterday from our U of AZ weather folk:

Yesterday’s movie has some interesting aspects.  Those morning Altocumulus clouds seem to be shimmering as waves in the air move through them.   Second, there was locust outbreak, or maybe a bee swarm, that was captured in this time lapse movie.  Its pretty funny.  They seem pretty upset; maybe like I was at the lack of clouds.

Lastly, right at the end, toward sunset, you will see MORE Altocumulus clouds moving in, but now from the east (or right to left), a completely different direction of movement than those morning Altocumulus.  That later movement represents a new surge of moist air into the Catalina region, and Mr. Cloud Maven is once again, undaunted by earlier error, and the many before that, will anticipate a Cumulonimbus on the Catalinas THIS afternoon.  Damn the models, full speed ahead!  Well, those models ARE indicating a greater chance of rain around, too.

Now, it may not rain here, but I really want to see one over there on Ms. Mt. Lemmon.  A day in July without a Cumulonimbus and thunder rumble is pretty tough to take!

Going to Biosphere 2 this afternoon, though if there is too much excitement outside, I won’t be able to go in.

Below, yesterday morning’s Altocumulus perlucidus at -10 C.  Notice that even though those clouds were well below freezing, that ice is not forming (which would be seen as fine trails of virga).

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.