Category Archives: Rainbows

Definitions, Rainbows

In case you missed it…

yesterday’s lightning criss-crossed rainbows over Catalina/Oro Valley.  Couldn’t capture the lightning, but two strokes occurred while this glorious rainbow was in progress.  Once again, being from Seattle, I have to say, “Never seen that combination before.”  I now really wish the University of Washington had had a branch campus in the Tucson area–go Huskies!   The first shot was taken at 5:49 AM, about the same time as the rainbow fragment in an earlier post.  You can see that the other part of yesterday’s rainbow is in EXACTLY the same position as that colored highlight shown back then.  It was odd, too, that there still was lightning with this very weakly, raining, and dissipating Cumulonimbus, and in particular, a cloud-to-ground strike.  Seemed to continue the regime of unusually electrified clouds in the past 24 h, ones that seemed ordinary, or even weak, yet produced prodigious amounts of lightning, and continued to flash long after they seemed “dead” as clouds.  That is, no new updraft areas apparent, just virga and weak rainshafts as shown here).    Hmmmmm…..

Nice, unexpected thunderstorm this morning with an extremely close strike here about 3 AM.  Total rain only 0.07 inches, but with an interruption of the summer rains predicted for several days, the mods say, any rain is welcomed!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Altocumulus clouds, Rainbows

In case you missed it-a spectacular, if odd, partial rainbow

Have never seen anything like this, shot taken about 5:50 AM LST yesterday, July 26th.  My best guess is that it was a partial rainbow, made possible by the small region of rain falling out of these Altocumulus opacus clouds.  Probably some bulges in those tops above where the rain is falling so that they reached the “glaciation” level, but then the precip as snow, melts into rain just below cloud base.  The low sun angle produces what would be the most gigantic rainbow ever, running about from due S to due N if complete.  Is that even possible?    The lower the sun angle, the dimmer the light, the larger is the arc of the rainbow.   Will have to research this some more.

Some further thoughts…  When you see VERY localized occurrences of precip from widespread cloud sheets like this, the possibility arises that it could have been created by the passage of an aircraft.   An aircraft, under certain special conditions, CAN create precipitation in supercooled clouds–there was global publicity on this phenomenon recently asserting that airports could be affected by aircraft in snow situations.   A friend was flying to New Hampshire yesterday out of TUS, and I wonder if her plane left this salutation?    Hahahah, sort of.  Most often, a hole in the layer is observed when that happens, and so the thought that it WAS an aircraft is somewhat suspect.

Go here, if you want to really get deep in this aircraft phenomenon.  (Yes, Mr. Cloud-maven himself was involved in the reporting of this phenomenomanonanon)

The End

 

Cumulus clouds, Definitions, Rainbows

The color of rain

In case you missed it last evening….   Don’t forget, too, that if you are standing in sunlight AND rain, that you are IN somebody’s rainbow.  In fact, whereever the sunlight is hitting the rain is somebody’s rainbow.  You can only see the one the laws of physics combined with drop sizes allow you to see.   So, in a sense, the rain you standing in is brilliantly colored; you just can’t see it.  Kind of cool, when you think about it.

Here’s the post mortem on yesterday.

First, morning Stratocumulus clouds topping Samaniego Ridge.  2) The occasional “sprout” of deeper Cumuli out of that mass.

 

 

 

 

 

 

 

 

But along with that, the Cumulus clouds elsewhere remained pretty flat (3), indicating there was something above the tops holding them back. That would be some sort of “stable” layer that would have to be overcome by more heating before any of these could surge upward farther and produce rain.  Below, taken at 2:15 PM yesterday afternoon.  With only occasional “sprouts” over the Catalinas that withered and died (4) instead of blowing up into thunderstorms, there was some reason for concern at this point.  In fact, NOTHING sprung up over the Catalina mountains.  Rain fell yesterday evening for a few hours, but we had to be “saved” from a dry day by a thundery mass, mostly the fading remnants of strong storms that marched westward from the White Mountains.  The last photo, (5) shows that “stratiform” cloud mass (with Cumulus underneath it) that brought the steady light rain and rainbows.  This photo was taken as the first drops began to fall.

Our rainfall was only 0.13 inches, but considering these masses often run out of rain before getting here, I was grateful for that.