This is great news, heard here first of course (haha), after a pitiful April with no measurable rain. Poor desert.
Its been suggested by the NOAA spaghetti factory for some time, but now actual precipitation is showing up in the models pretty regularly for around May 8th and thereafter, and so we can gleefully start dusting off our umbrellas, seeing if we have enough change for the car wash afterwards, etc.
Even WU (Weather Underground) is starting to catch up, showing about a 3% (THREE percent!) chance of rain at that time from last night’s model output. Its “waymore better” (a nice name for someone) than that, I think, though its not 100% yet. That percentage should be climbing as the days get closer.
BTW, Have never seen such a pronounced “retrogression” as that shown today over such a vast region of the globe in those spaghetti plots, and that’s why I’ve taken to the air today.
The good news for AZ-ians is that we get placed in a trough in the lower latitudes, albeit a weak one; a dip in “jetty jet stream” to the south over us (meaning cooler temperatures than average aloft should prevail) with some enhanced chances for rain after our main chances coming right up on the 8th and beyond for a couple of days.
As you know already, ovenly weather for this time of year, with temperatures far above average, is just ahead, which takes a big, fat high pressure dome aloft over us. That high will dissipate as “troughy” conditions begin to shape up toward the weekend.
So, venturing farther, it would seem a reasonable temperature first half of May is ahead, with RAIN, after the “meltdown” later this week.
Time for a random thought before closing:
A cactus can be a beautiful thing, can’t it?The End
Honestly, I gave up on the chance of rain overnight into this morning at sunset yesterday due to the absolutely clear skies. And, like you, woke up to not one cloud within a 100 miles! How could this be, given the synoptic situation? Started slicing apples for some humble pie, but then, when looking at a radar and cloud loop (this one from IPS MeteoStar) saw that lower clouds had magically erupted to our west before midnight, and by the time they got here in the early morning hours, had little showers coming out of them!
I did not park my own dusty car out from the carport, either. I thought I would at LEAST see a pile of clouds on Ms. Lemmon, too, this morning! Sure wrong there. Here are a couple of images from what has to be considered a tiny weather miracle:
Chances of rain increasing (imagine!), for just over a week from now as actual model outputs begin reflecting what spaghetti (the many outputs) was indicating, i.e., a big upper trough in the West-Great Basin area. At the time that spaghetti was indicating that, the actual model outputs were not, indicating that they were outliers.
Check this out from last night. Since this model output is more in agreement with that crazy spaghetti plot, it inherently has more credibility, and is likely not an outlier model run. That what the NOAA spaghetti factory is used for, getting a handle on those runs that might be wild, and those that are more likely to verify.
Its valid on the morning of May 8th and shows a trough coming out of the Pacific ahead of the one from the Pac NW, shown at this time over northern Cal. The hope here would be that the one from the SW would have a generous amount of sub-tropical clouds with rain in them.
Cloud shots will be posted later this morning of the next day….. (i didn’t get to is as I had planned)
Yesterday afternoon, the 29th. Here’s what shallow, icy clouds look like, reflecting the unusually cold air above us.
PS: Chance of rain still holding for the 8th. See below for new depiction of big “cutoff” vortex over AZ from last evening’s model run:
The orangy colors denote the strongest winds in “Jetty Jetstream”, and as you know, the colder, low clouds, ones capable of reaching the temperatures where ice forms, are contained within that ring of strongest winds at this level (500 mb). So, while the models I have looked at so far have no rain here, I think there’s a pretty good chance of a rogue shower tomorrow morning anyway. At least there should be some nice Stratocumulus/Cumulus tomorrow and some will have ice in them. As you know, it’ll be awful windy today, too, maybe 40 mph or so in brief gusts here in The Heights of Sutherland.
Also will be looking for some nice lenticulars since “Jetty” will be right over us, but a little toward the warm side where lenticulars mostly occur.
In the meantime, spaghetti suggests a big trough in our area again about nine days from now. The later ACTUAL model outputs don’t show much of anything. What’s up with that? I’m hanging with spaghetti that later model runs will indicate a strong trough, and at LEAST another pulse of cooler air, and another minor chance of rain as we are going to see today and especially tomorrow as when become within the “ring of winds” aloft. Didn’t Johnny Cash sing something about that? Maybe it was Wall of Voodoo…
Below, some spaghetti for you showing a big trough over Arizona and the Great Basin which is not much reflected in the actual models, as noted. But, just watch my friend, how those model outputs will change to reflect a bigger trough about this time!
April’s been kind of a weather dud here in Catalina so far (no rain so far, and the chance on the 20th, mentioned here some weeks ago, has receded to Utah and points north), so lets take a look at how May is shaping up, only two weeks ahead:
I thought you’d be pretty happy when you saw this, as I was.
Its possible there is a photo from Catalina, Arizona! I have not checked yet. Its just been published by the World Meteorological Organization of the United Nations. Still needs a little work, but overall is VERY, very nice. Came out out on March 23rd, so we’re a little behind here as usual. The thing that makes it different from prior and sometimes flawed atlases is that each photo is accompanied by some weather data and in many cases maps, radar or satellite imagery at the time of the photo.
Some new expressions to toss around to your fellow cloud-centric folk are things like “Cirrus anthrogenitus”–Cirrus evolved from contrails and “Cumulus flammogenitus”, a Cumulus formed at the top of a fire, something we used to call, “pyrocumulus”, an unofficial term that somehow seems preferable to “flammo”.
However, something that has drawn great attention over the past 20 years or so was not given a name, aircraft-produced ice in Altocumulus and Cirrocumulus clouds, which have been referred to by Heymsfield and colleagues as “hole punch clouds.”1
Ice canals amid Altocumulus are also fairly common. Ironically, a hole punch cloud with ice in the center, and an ice canal in an Altocumulus cloud layer can be readily seen on the new International Cloud Atlas submission site, now closed. They’ve mistakenly, IMO, referred to “ice canal” photos as “distrails” without mentioning the ice canal “cirrus” down the middle. Formerly, distrails were clearings produced by aircraft in thin clouds without any change of phase in the cloud induced by the aircraft, unlike those holes and clearings produced when the ice-phase is triggered by an aircraft passage.
Certainly a “hole punch” cloud is not a distrail, a linear feature, and should have a separate nomenclature.
In keeping with the new terminology regarding “anthro” effects, maybe it should be, since we’re talking about the Cirrus induced by an aircraft, albeit at much lower levels than true Cirrus clouds:
“CIrrus Altocumuloanthroglaciogenitus.” (??)
Here’s a classic one of those that erupted over Catalina, posted here last January:
——————————————- 1It should be pointed out immediately if not sooner that Catalina’s Cloud Maven Person had plenty of time to rectify, or suggest changes to the Atlas as he could have been part of this process, but didn’t really do anything except submit some images for consideration.
I could literally hear the cameras clicking all over Catalina and Oro Valley as these patterns showed up, moving in from the southwest as the increasing numbers of cloud-centric folk lost control of themselves. Reflecting that general loss of control, which affected yours truly, too many photos will be posted here. Below holey clouds with icy centers, but not ones caused by aircraft:
And look closely at the fine patterns, lines and granulations in these shots! Truly mesmerizing.
But what’s missing in this photo above? There was no iridescence seen around the sun where we normally look for it suggesting that those Cirrocumulus clouds nearest the sun were composed of ice crystals, and not tiny droplets. Iridescence is rarely seen next to the sun due to ice crystals because they are usually the result of the freezing of existing droplets, that then grow rapidly as ice particles to sizes too large to produce diffraction phenomenon close to the sun. Where’s my Lear jet, so’s I can confirm these speculations?!! I would very much like to have one on “stand by”, in case I think of something. Below, a wonderful example of no iridescence even though newly formed clouds are by the sun:
A jet runs through it
Or so I thought. In this chapter of cloud-maven.com, we inspect the photos of a commercial jet flying at or near the level of these clouds and determine what happened. I was quite excited to see this happen because we would now determine whether there were any liquid droplets in what to the eye of the amateur cloud watching person would be a liquid droplet Altocumulus clouds. Here the size of the elements are just a bit too large to lump it into the Cirrocumulus category, if you care. So, with heart pounding, took this sequence of photos:
Let is go zooming:
By the way, if you caught it, there were a couple of standard, aircraft-produced, “hole punch” clouds at the very upwind, formative portion of this patch of clouds before it got here. These photos pretty much prove that the Cc at the formative end at that time was composed of highly supercooled droplets and that the passage of an aircraft produced ice, that caused a fall out hole.
In particular, those Altocumulus clouds, “cold” Cirrocumulus (ones that transform to ice immediately), and those “Altocumulocirrus” clouds combining with scenes of “regular” cirriform clouds. Lots of interesting sights to have seen yesterday. All these the result of marginal moisture aloft and strong winds, up around 100 mph at the highest Cirrus levels.
Let us begin as cloud maven folk by examining the late afternoon sounding launched from our Wildcat balloon launching machine at the University of Arizona, courtesy of IPS Meteostar:
The weather way ahead
Still looking for that chance of rain before July…. haha
Troughy conditions will actually recur aloft over us over the next few weeks it seems, which means slight chances of rain, but periodic cold fronts passing by, mostly dry ones. Best chance for rain still seems to be around the 20th, plus or minus a day or two, even though mod outputs have backed off that scene. But, we have our spaghetti that tells us the models will likely bring back that threat around the 20th, even if some individual runs show nothing at all or only close calls. We shall see if this interpretation has any credibility at all, won’t we?
Of note, Cal having big April in rain and snow after the gigantic January and February accumulations! Looks like they’ll continue to get slugged by unusually strong storms, off and on, for another couple of weeks. Water year totals are going to be truly gigantic.
Cooling off now after the Big Review of NAS 2003…and finally getting back to the lighthearted, carefree, playful, well, silly, mode normally found here (he sez).
As a brief follow up, I have yet to receive a “thank you very much for your absurdly late review of our tome on cloud seeding; had you submitted it in a timely manner, perhaps one thing you wrote MIGHT have been considered” note from the National Academy of Sciences for all the work I put in on it. Must be pretty busy back there.
Also, if it didn’t go out “like a lion”, as foretold here weeks ago utilizing weather lore, March at least went out as something of a “bobcat” with the severe winds, series of cold fronts, we Catalinans experienced, along with several traces of rain. “In like a lamb, out like a bobcat.”
The weather way ahead
Spaghetti lovers will INSTANTLY recognize from those maps, of which ONE is shown for April 20th, that other than wind and “fluctuating temperatures” as dry cold fronts pass by, that there’s no chance of rain until the 20th. Check it out if you don’t believe me again:
I put up a new page on this blog (see top header for “pages”) for sciency types deeply interested in weather modification/cloud seeding, my main avocation “whilst” working in the met sector. Its a many “commented out” review of NAS03 (shorthand for the National Academy of Sciences tome, published in 2003, “Critical Issues in Weather Modification Research.” I also post it here for redundancy. This is what I have been doing lately instead of reporting to you on clouds and dust.
The original document as long, and with insertions and commentaries, well, now what’s here is over 170 pages. Only the weather mod technocrat among you will truly be interested. I found a couple of errors, and have done a little re-writing just now (April 4th).
Why this review is so late is explained, in fact, I tell “all” the good and the bad and delve into, oh, controversy. Its not in the usual style of this blog, of course, since its a highly technical review.
Some background, if you care
My first job in the cloud seeding domain was with North American Weather Consultants, Goleta, CA, one of the oldest cloud seeding companies in America. I was a student hire for the summer of 1968. I was coming off my Junior year at San Jose State. Robert D. Elliott was president and founder of NAWC, which he founded soon after Vincent Schaefer’s stunning dry ice experiments showed that you could cause snow to fall out of supercooled droplet clouds when you converted them to ice crystals. That precip-forming process is known as the Wegner-Bergeron-Findeisen process.
The remarkable event of that summer was that “Bob’s” friend, Tor Bergeron, (of the Wegner-Bergeron-Findeisen mechanism of rain formation) came one day to visit Bob and I got a photo taken with him! In case you would like to see me with one of the “Fathers of Rain”, Tor Bergeron , or Tor himself, here it is ( I laugh when I look at this; can pants be any tighter?):
I loved that job and the people there! Cloud seeding was so interesting, too! And I already about 20 years into my cloud-centric life, had chased thunderstorms in the southern Cal and Arizona deserts, and a hurricane in 1961, Carla, by then. I knew what ice was in the sky.
Things kinda went downhill for me in the cloud seeding arena not too long after that when I joined, as my first job out of college, the Colorado River Basin Pilot Project, a massive randomized cloud seeding experiment that was going to replicate stunning cloud seeding successes published by scientists at Colorado State University. Winter snowfall in the Rockies had been increased in certain situations by 50-100% in their own randomized experiments! And the CRBPP was going to target those situations in the random decisions.
I started out as Assistant Project Forecaster in the fall of 1970, and then after some early personnel shuffling, was booted up to “Acting Project Forecaster”, forecasting the weather EVERY day, and calling all the random decisions that first season! There was no “Assistant Forecaster” any longer. I loved it! Couldn’t wait to get to work!
If you don’t believe me that I forecast the weather for random draws in the massive Colorado River Basin Pilot Project cloud seeding experiment right out of college, then you’ll have to see this “documovie” in which I make a forecast, filmed in the late winter of 1971, and one that premiered in Durango, CO, in 1972 (not ’81 as this youtube site claims)1:
It was SO EXCITING being a part of this grand project! And who wouldn’t love Durango, Colorado?
But, it turned out that there were lots of problems with the Colorado experimenters hypotheses, and those problems weren’t getting outside of the BuRec and our group. The wider weather modification community, which so highly regarded the experimenters’ experiments so highly, remained ignorant of those problems.
Well, during the five years I worked on that project, moved back to “Assistant Project Forecaster” when the second one, Owen Rhea, left after one season and a new Project Manager brought in his own forecaster.
It was later in those five years in Durango with the CRBPP that I abandoned my original Master’s Thesis at San Jose State on southern Cal rainfall trends, and took on reanalyses of cloud seeding experiments, something that was to go on for the next 35 years or so as “non-funded work”; weekends, and evenings, mornings before the regular work day at the U of WA. I was even drafting my own figures in the manuscripts I produced!
I was consumed, as I have been lately, by the lack of reporting, and even false claims in a journal article relative to our CRBPP project in those Durango days, by authors who knew better. It was truly melodramatic, but I felt someone had to do something about this!
As a cloud watcher, one of the very main things missing from the experimenters’ claims, was the presence, for hours at a time, of thick, non-precipitating clouds, ripe for seeding, with tops > -23°C, very cold ones. Instead, the clouds impacting Durango and the surrounding mountains were full of ice, as any cloud watcher could see. There was no such cloud as the experimenters had inferred via statistical analyses.
Cloud seeding they wrote, had not INCREASED the intensity of snowfall in their experiments they reported, but must have made it fall from clouds that did snow naturally until seeded. The only evidence they had for the existence of such clouds was that it had snowed longer on seeded days than on control days.
Not only that, seeding had made them snow at exactly the same rate as natural snowfall. It was a huge red flag for a storm bias in their experiments, a “lucky draw” or “Type I Statistical Error” for the seeded days.
And that’s what had really happened, among many other pitfalls, as you will read in the linked “review” above.
In conclusion: you can do a lot over a LONG period when you’re worked up about something!
——————————– 1Yes, it was a cloud seeding experiment so important, so much optimism around, it had its own movie! And it had a score by local guitar master, Clarence “Gatemouth” Brown!
On this station plot map for the Tucson area, generated by the University of Arizona’s Hydro and Atmospheric Sciences Department, now has a point for little Catalina/Sutherland Heights! Check it out. Sample map below. Now you can see how our predicted weather varies with those points around us over the next few days. How great is that?Some rain from our incoming cold front is just about here as a line of showers approaches from the west. Hoping now for a tenth of an inch is all.
Had some nice scenes late of little Altocumulus castellanus shedding light snow showers or “virga.”
The weather ahead and way ahead
March. a lamb upon entry, will roar on the way out. While only a little rain will likely fall today, several more troughs are in the works, during the next ten days and they are looking much more potent than today’s trough and front passage, probably bringing cold enough air that some people will start complaining about how cold it is; probably me. Looks, too, like abnormally cool weather will cruise right in to the first week or two of April. Bye-bye heat!