Thunderstorms pound Catalina/Sutherland Heights with 0.01 inches of rain! Blog contains a horse photo!!

Well, a partial shot of a horse….

A horse photo will always enhance a blog about clouds.  Expecting a little uptick in readership due to this ploy,  maybe will break out of the single digit  column.

Not much happened early on, a thin film of Cirrostratus covered much of the sky, delaying the expected development of convection, as would be evidenced by the formation of Cumulus clouds, until mid-afternoon.

But they did form, mostly to the S through W of Catalinaland,  upwind of us, and eventually rumbled in on their last legs as weak thunderstorms with gushes of sprinkles and gusty breezes, maybe ones over 15 mph!

Over there in Marana and Avra Valley, those places upstream of us, some spots got more than half an inch.    But, i it seems this year that storms die when they move toward Catalina, and especially, toward MY house and its many raingauges (3).

Still, it was nice to feel cool breezes, air chilled by falling rain, even if elsewhere.

Here are a few dull and disappointing cloud shots from yesterday, including one with a horse:

DSCN1692
10:56 AM. Horse looks ahead, examining the vellum of Cirrostratus cloud overhead, wondering if it means anything. If this was Seattle, such a layer would thicken and lower into a steady rain within hours 70% of the time. Pretty true for most higher latitude locations in the cooler time of the year. (This was horsey’s first true trail ride, going up and down rocky gullies with loose rocks along side the Sutherland Wash. Previously this horse had spent most of its 14 years in a small corral so this was all pretty new to him;  rider tension high.)
DSC_8895
2:49 PM. A soothing gray of Altocumulus undercut the layer of Cirrostratus. Building Cumulus clouds can be seen toward the Mexican border on the horizon. Pusch Ridge is in the foreground. As you can see, no virga is falling from those Altocumulus clouds, so they must be pretty “warm”, warmer than about -10° to -15° C at cloud top.
DSC_8897
3:38 PM. Looking suggestive of rain here in Catalina. However, these storms were in the late, dissipating stage. Note too how the anvils have merged with the Cirrostratus layer and lean far out from the storms toward us, helping to cool the ground, ruin the chances of new Cumulus buildups ahead of them.
DSC_8900
4:19 PM. Not much going on over the Catalinas. Notice how broken up into light and dark patches these otherwise dark looking lower clouds are. Shows there’s no hope for any buildup out of them, though, lower clouds like these under precipitating Altostratus cumulonimbogenitus (that higher cloud here which is really the result of anvils) can help sprinkles get to the ground. That’s because drops or snowflakes falling out of the higher cloud, won’t evaporate while falling though these clouds (representing saturated air with respect to water).
4:33 PM. Nice shaft, some cloud-to-ground lightning strokes toward south Tucson, but who cares? Wasn't moving this way, and would be mostly dissipated by the time it got here anyway.
4:33 PM. Nice shaft, some cloud-to-ground lightning strokes toward south Tucson, but who cares? Wasn’t moving this way, and would be mostly dissipated by the time it got here anyway.
4:57 PM. Eventually some rain with an occasional lighting outrage did reach the southern parts of the Catalinas, making it all the way to Ms. Mt. Sara Lemmon, and SPKLS fell in Catalina.
4:57 PM. Some rain with an occasional lightning outrage did reach the southern parts of the Catalinas, eventually making it all the way to Ms. Mt. Sara Lemmon where 0.24 inches was recorded.   SPKLS fell in Catalina.
5:42 PM.
5:42 PM. Last gasp, last chance for rain here, dying shower with some new bases to the right, offer another slight hope that the new stuff will develop into showers like this one.  It didn’t.

Still have rain chances last few days of Oct into early Nov.

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.