Yesterday’s drama, forecasting for picnics, etc.

In case you missed it, and you probably did because you were still in bed while I was doing things for you, there was a pretty sunrise to start the day yesterday, one that would not disappoint later by being a dry one.  After all, we’re here in the peak of our summer rain season.

 

Got 0.27 inches here, and 0.40 inches in Sutherland Heights.  (The U of AZ rainfall network will have lots of data, some places getting over an inch yesterday. Pima County amounts here.)

 

BTW, as mind wanders, the real monsoon in India is a a little below normal this year so far.   But, check out these forecast maps from IPS Meteostar and look at the west coast of India.  It rains every day all day for the 15 days of the computer model run.  Nothing really too unusual about that, rain every day all day on the western Ghats, 10-20 inches a week. Now THAT is a monsoon!  Thought you might like a little distraction, get you out of any ruts you might be, get you thinking “outside the box” for a change.

 

OUR story, the long and winding one, continues below, though it can be seen in totality, in the short form in the U of A time lapse movie.  This is a great U of A movie, with several “dump trucks” going by.  Its amazing how much water can just suddenly be unloaded by a cloud!

 

Also, lenticular clouds (hover clouds) can be seen at the beginning and end of the movie downstream of the Cat Mountains, unusual for summer.
5:27 AM. Altocumulus opacus, no snow virga. What’s the top temperature? Hint: warmer than -10 C (14 F).
7:27 AM.  You’re finally up and you see this grayness due to Altocu/Stratocu.  You start to fret over whether it can rain later in the afternoon with all these clouds keeping the temperature down.
10:32 AM. Your mood begins to brighten just like the sky;  the temperature is soaring while the mid-level clouds thin, and Cumulus begin arising over Ms. Lemmon, trailing overhead toward YOU.  You feel special.
1:32 PM. You’ve been patient, and FINALLY the clouds trailing off Lemmon are beginning to look like they might erupt into Cumulonimbus ones;  bases are firming up, coalescing.
1:58 PM. Its looking really good. Nice compact bottom almost overhead. You’re getting euphoric, well, hopeful.
2:00 PM. Only TWO minutes later and the load is on the way down! This is the time you want to be at a picnic 2 minutes earlier and amaze people by saying, “RUN for your car! NOW!”, though they probably wouldn’t pay any attention to you unless you knew them and they knew you were cloudcentric.
2:02 PM. Picnic’s over.
2:03 PM. ONE minute later! The Fat Lady has sung.
2:19 PM. Downspout from Cumulonimbus cloud moves on across to Oro Valley to “excite” other picnickers.
2:22 PM. This beauty off to the north. Name? Cumulonimbus calvus (fibrous nature of top not yet fully evident, though a practiced eye can detected the cotton candy ice composition in the two pronged top. In front of it, a Cumulus congestus. Check that shaft!  What day! Fantastic scenes all around.

 

 

 

 

 

The weather ahead.

U of A mod results not yet available at this hour (5:08 AM), but other model outputs suggest another three days, including today, of the kinds of scenes shown above.
Every day will be that bit different in shower coverage, of course, that governed by subtleties in the flow aloft, grade of moisture supply, dewpoints, etc.

But those days ahead will be great enough, our deserts being drenched here and there, the desert foilage exploding.  Enjoy those clouds while they’re here.

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.