You have to work with what you have. Imagine a day without crime, or an exploding balloon, traffic accident, tax folderol, etc., and the television news for that day is cancelled, not worthy of air time, maybe replaced with one of our favorite PBS programs, like, “The Desert Speaks”?
Had a nice lenticular a couple of days ago, in case you missed it.
Let’s face it, for most of the people living in Arizona, their best years are in the rear view mirror, as are mine which were probably about 50 years ago… Following that thought, let us not look ahead to further declines, but rather look back at the last water year for Catalina, ending this past September 30th, and see what it says, if anything, about the changing global climate we hear so much about:
Can’t say I see too much going on here in Catalina so far; things seem pretty stable in the precipitation arena for the full water year’s rainfall.
I point out again, with great redundancy since I have pointed this out before, that the Our Garden climate record started just as a monumental change in circulation patterns occurred. Most climate scientists would attribute that to a shift as due to the Pacific Decadal Oscillation, discovered by important scientists I know well, like Mike Wallace1, of the University of Washington Huskies Atmospheric Sciences Department where I worked for about 30 years, but in airborne studies of clouds.
The PDO shift, if that’s what done it, was a circulation pattern change that brought astoundingly wet conditions to Catalina and the whole Southwest US, wet conditions unlikely to be seen in our remaining lifetimes, which aren’t that much longer anyway.
You may remember that bristle cone pine tree rings in California, analyzed by Haston and Michaelson in 1994, found only one period in the last 600 years (!) that was as wet as the late 1970s into the 1980s there (certainly spilling into AZ).
Remember how the Great Salt Lake was filling up to record levels back in the 1980s?
And any long term resident here, like the ones that I have spoken to, will tell you about the days of yore when the washes around here were running all year.
Well, that wasn’t the norm. sadly. They were just so lucky to have seen that era.
In weather, what goes around, comes around. Count on it happening again at some point in the future IMO. (Some climate changers might disagree with this assertion.)
How about our summer rainfall, June through September. Well, here’s that graph, updated through this past summer! Hope you like it:
Not much going on here, either.
Yesterday’s clouds–another day, another rainbow, of course.
Sprinkles of rain occurred off and on all day yesterday, but couldn’t muster even one hundredth of an inch of rain! With a few exceptions, the clouds producing the rain weren’t too deep, though still icy ones, and pretty high off the ground, mostly above 8,000 to 9.000 feet above us, which doesn’t help.
First, a rainbow shot:
1Well, actually we said “hi” in the halls once in awhile, I gave a talk in his class once, and, along with a bunch of Atmos Sci faculty, got to watch the 1992 New Year’s Day Rose Bowl mash down of Michigan for the Washington’s 1991 NCAA Division I fubball championship at his house. He also mediated an authorship kerfluffle between Peter Hobbs and me.
Just back from a horsey ride with Zeus the horse. Rode into the CDO to see the surprising view that it had run bank-to-bank last night after that mighty cell passed by along the foothills. In the wash, were golf ball-sized golf balls scattered throughout the wash, indicating that it hit the planned community of Saddlebrooke with it many golf courses very hard. No golfers were found.
The Pima County ALERT gauges really did not call out that such a flow would occur from precip data around here, the greatest amount being barely over an inch, and its likely that such a flow in the CDO, bank to bank would need 2-3 inch dump in its watershed.
———-end of updated material unless I get more updated——
After an afternoon of “steady-state” Cumulus congestus and small Cumulonimbus clouds trailed northward from the Catalina Mountains, the “Mighty Kong” erupted about 5 PM providing one of the most intimidating, yet majestic and beautiful scenes of the summer rain season; this or any.
Cloud Maven Person was indoors drowning his sorrows concerning what appeared to be a a grotesquely failed forecast of a good rain day (“about half an inch”) here in Catalina in flavorful Indian cuisine when the unexpected began to take place outside. So, the photo record is incomplete for this event. “CMP” had given up on the day.
Just measured in NWS-Style 8-inch gauge and CoCoRahs gauge:
0.12 inches was our total here in the Heights.
And, the photos aren’t quite as good as they should be, slightly out of focus since CMP didn’t adjust his camera for the dark scenes his was seeing. Oh, me. Missed the great sunrise, too, due to not having memory stick in the camera! Oh, me.
However this line faded, bringing only sprinkles, a trace of rain to Catalina, and was followed by a huge clearing and sunny skies, thought to be a good thing at the time. Soon, gigantic Cumulonimbus clouds would erupt to over the mountains all quadrants… Nope. By mid-afternoon, only Cumulus congestus had formed with an occasional bit of ice and rain visible, all to the north.
This was the last photo I took until walking out of a local Indian restaurant and exclaiming, “What? When did this happen?” It was so clear to the S-W with the exception of a single dissipating Cb that it didn’t even seem worth a photo.
Well, as it turned out it was a near hit, only 0.06 inches fell in a violent few minutes of huge drops at my place in Sutherland Heights. From what I saw going by, and needing 0.44 inches on yesterday morning’s forecast of 0.50 inches in Sutherland Heights. about 500 yards farther west for this remarkable, dramatic storm would have given us that amount easily. 1.06 inches was recorded at Cargodera Canyon, NE corner of Cat State Park, and several sites in the foot hills of Catalina toward the mountains area had more than half an inch.
A quickie take on a U of AZ model run from last evening’s global data, has Cumulonimbus clouds developing to our southwest and rolling across Catalina in the afternoon. This would be, appropriately, considering the definition of the end of our summer rain season as September 30th, very appropriate.
Some apocalyptic cloud scenes can be Cumulus that explode suddenly into Cumulonimbus, and Cumulonimbus clouds with their foreboding (unless you live in a desert) rain shafts, and their predecessor shelf clouds like “swirly dark Stratocumulus”, and arcus clouds, the latter, a lower line of clouds just above and a little behind the wind shift at the ground, usually just ahead of the main rain shaft. While we didn’t get to see an arcus cloud yesterday, we had some dramatic swlrly dark Stratocumulus clouds to scare us. I say “swirly” because if you looked up yesterday evening as they passed over, you would have seen rotation in them.
These can combine, as they did yesterday, to make you think someone might drop out of the clouds and fix the world1. See those scary photos below, way below as it turns out.
This monster collection of Cumulonimbus clouds (“mesoscale convective system” or MCS in weather lingo) with swirly shelf clouds preceding it barged over Catalina later yesterday afternoon after it appeared that not much was going to happen all day. Heck, there wasn’t even a decent Cumulus over the Catalinas until after 2 PM!
The result of this system slamming Catalina was the usual strong preceding winds roaring down from Charouleau Gap way and points north or northeast. The winds were not as damaging as three days earlier.
Then the rain! So nice! Got 0.55 inches of rain here in Sutherland Heights, an inch and half on Samaniego Ridge, and 1.65 inches on Ms. Lemmon.
Worth watching is the U of AZ weather departments time lapse video, especially beginning at 2 min 50 s into it. That’s when the big group of Cbs begins to make its presence known from the east. What is interesting, and what I have not seen before, is that you will see the tops of a thunderhead farther west, that icy part up around 30,000 to 40,000 feet, shoved backwards (back toward the west) by outflow at the tops of the huge incoming system. Very dramatic.
Detour: detecting ice in clouds….some practice shots
As the burgeoning cloud maven junior person you, of course, know how important the appearance of ice in our clouds is. You got ice; you got precipitation, which is snow up there, soft hail, hail, frozen drops.
Only the largest hailstones up there can make it to the ground as such here in Arizona due to our high summertime freezing levels. The rest melt into raindrops, some of which are large enough to reach the ground. Those downpours that suddenly emit from cloud bases were always hail or graupel (soft hail) aloft.
Sometimes in deep stratiform clouds attached to clusters of Cumulonimbus clouds, and with especially moist air from the base of the stratiform layer to the ground, clusters of ice crystals we call snowflakes make it to the ground without evaporating as steady light or very light rain.
Last night as our storm was coming to an end, it is likely that THOSE drops were once snowflakes rather than soft hail or graupel.
The End (finally)
1Huh. Maybe that wouldn’t be a bad thing. I am very concerned about microplastics (particles 5 millimeters and smaller) in our oceans, resulting from the breakup of larger plastic items we’ve been throwing in the oceans for decades. Seems those tiny particles are getting into everything, including the fish out there! It would be great if someone could get rid of them.
Have had 1.75 inches here in the Heights last few days. Horsies are tromping around in significant mud.
But, to resume a theme about others from the prior entry, those in California, they’d better be paying close attention to the weather a week and more out. In this weather watcher’s opinion, which should count for something, California may be in for an unforgettable January.
Recall how those “ensemble-spaghetti-Lorenz” plots had an unusually constrained (contours of flow, red and blue lines that were unusually bunched together all the way from Hong Kong to ‘Frisco even 10-15 days out? That indicated a high confidence forecast of where the jet stream would be.
USUALLY, the contours are pretty wild, scattered all over the eastern Pac after about 10 days or so, and Cloud Maven Person got overly excited about this esoteric part of weather forecasting, and decided to write a partially decipherable tome on it.
Well, that constrained jet, blasting into Cal from the subtropical latitudes with a terrible ferocity, has continued in model run after model run now, and CMP’s excitement has been further elevated, maybe to penthouse level now, hard to elevate it more.
Way below are a few examples from just last night’s model run based on global obs at 5 PM AST, showing a few sample of the jet stream predicted pattern at 500 millibars, or around 18, 000 feet (from IPS MeteoStar, as usual).
THESE are extraordinary maps, and extraordinary maps mean extraordinary storms, AND they are appearing with extraordinary consistency.
They are also compatible with what we saw in those ensemble-spaghetti plots of a few days ago. So, like the “Frankenstorm” of 2010 that hit California, this series of strong storms hitting Cal in just over a week, will be considered to have been “well-predicted” by those crazy plots.
Is FEMA ready?
I think they will be involved at some point.
But, too, this is a forecast series where we (those in Cal) have lots of time to get ready for big, destructive events.
For Cal, the usual.
1) Huge waves smash the coast, some home roll into the ocean. With a jet having a gigantic fetch from the Pac, huge waves are a certainty, surf will definitely be up, if that’s what you do because the surface winds will ALSO have a huge fetch to build those giant rollers.
2) Winds. At some point, hurricane force winds blow stuff around in one of more of the low centers generated by such a powerful jet stream. Looking at the pattern, I think one within this storm series may produce 100 mph winds or more somewhere in Cal.
3) Flooding. Can the nearly empty Cal reservoirs we’ve heard so much about be filled up in a series like this, something that might go on for one to two weeks? I think so, some anyway. But this is a truly wild thought, and as you can see, CMP is kind of out of control here.
It is certain that the rains with one or more of the low centers that slam the West Coast during this series will produce rains of 10 or more inches in a day in the hill and mountain regions of Cal.
Also, the series begins with a strong, but maybe not exceptional storm about 8 days from now, this after a pretty good rain has already occurred, so the ground is going to be pretty wet when the Big Series hits.
The jet stream pattern strengthens and shifts farther south with each day after this first major storm, and that’s when the real onslaught will hit.
I don’t want to get people overly excited like I am, but I am terming these, and the whole recent series of unbelievable jet streams bashing into Cal, and even Baja!, “the California calamity maps.”
Skipping ahead some more….
Now the timing of these things WILL VARY as the mod runs keep churning out results, but in CMP’s view, the pattern that will cause CA havoc is locked in now, promulgated ALMOST without doubt by our Big Niño.
Here is another amazing map from a prior run, that just makes your jaw drop due to what the models are sensing is “out there” for Cal and the West Coast:
How will SE AZ do?
Seems like passing rains will hit during this CA bludgeoning period, but floody weather not expected.
Since we’re pretty much at our average total for the month of January right NOW, CMP is going out on a limb and predicting an above normal total for the WHOLE month.
This was amazing. I approach one of the puddles on Equestrian Trail. I see that its raining HARD in the puddle. I am only 20 feet from it, but its not raining on my car! Here’s what that scene looked like:
How could this be? Of course, we’ve all seen heavy rain on the road and drove into it. But the illusion here that was so striking is that it only SEEMED to be raining in the puddle, not around it since the drop splashes were not obvious as I drove up to it.
The rest of yesterday was pretty great, too, lots of rainbows, brilliant clouds and skies, too photogenic for a neurotic-compulsive photographer. However, one of 221 photos was of a human, a neighbor, not of clouds and rain shafts.
Here are a few too many cloud photos; excess is kind of a specialty of mine:
Lightly looking ahead
Still a lot of “troughy” weather ahead, and chance for decent November rains in the first half of the month after cold one goes by, followed by a short dry spell.
After last evening’s surprisingly heavy rain, we have now met our average for May for Catalina, having received 0.47 inches of rain over the past 24 h, some 0.36 inches during some house-shaking thunderclaps last evening.
Below are the 24 h local totals, ending at 4 AM today from the Pima County ALERT gauges rolling archive , these totals pretty much capturing all of our beautiful storm:
Gauge Location ID# —- —- —- —- —- —- —————– ——————— Catalina Area 1010 0.63 Golder Ranch Horseshoe Bend Rd in Saddlebrooke 1020 0.83 Oracle Ranger Station approximately 0.5 mi SW of Oracle 1040 0.55 Dodge Tank Edwin Rd 1.3 mi E of Lago Del Oro Parkway 1050 0.75 Cherry Spring approximately 1.5 mi W of Charouleau Gap 1060 0.79 Pig Spring approximately 1.1 mi NE of Charouleau Gap 1070 0.39 Cargodera Canyon NE corner of Catalina State Park 1080 0.63 CDO @ Rancho Solano CDO Wash NE of Saddlebrooke 1100 0.35 CDO @ Golder Rd CSO Wash at Golder Ranch Dr
Santa Catalina Mountains 1030 1.18 Oracle Ridge Oracle Ridge, 1.5 mi N of Rice Peak 1090 0.35 Mt. Lemmon Mount Lemmon 1110 1.34 CDO @ Coronado Camp CDO Wash 0.3 mi S of Coronado, 1130 0.83 Samaniego Peak Samaniego Peak on Samaniego Ridge 1140 0.79 Dan Saddle Dan Saddle on Oracle Ridge 2150 0.24 White Tail Catalina Hwy 0.8 mi W of Palisade RS 2280 0.24 Green Mountain Green Mountain 2290 0.12 Marshall Gulch Sabino Creek 0.6 mi SSE of Marshall Gulch
A little cold morning rain, and even snow on The Lemmon, is looking likely for Saturday morning. Presently, the core of the jet stream at 500 millibars or around 18,000 feet associated with a mighty upper cold low that sits on Arizona on Saturday is forecast to be south of us (as was yesterday’s jet), a pretty black and white discriminator for cool season (Oct-May) rain here.
However, if that jet core around the low does not circumscribe TUS, you can forget rain. From IPS MeteoStar, this rendering of the upper level configuration for Saturday morning, showing that it WILL circumscribe TUS:
In the meantime, “troughiness” today, tomorrow and Thursday, with secondary jet stream to south of us, will give us some more photogenic high-based Cumulus, maybe with some with virga in the afternoons. Today, as our upper low says goodbye, subsiding air is supposed to keep clouds from attaining tops high and cold enough to form ice. So, no rain today.
Yesterday’s clouds (going deep, as in pedantically)
There were some great scenes yesterday, summer-like ones, odd for May here, with massive rainshafts as the cloud bases lowered, reflected a huge jump in surface dewpoints to summer-like values in the mid-50s. Cloud bases yesterday morning, riding the tops of Samaniego Ridge, were near 7 C, compared with -5 C the afternoon before.
This warming of cloud bases greases the precipitation “wheel” since clouds with warm bases are be able to rain easier than ones with cold bases (say, near or at below freezing temperatures). Droplet sizes have to be larger at any given level above cloud base compared to the clouds of the day before since more moisture is forming in those updrafts at the higher base temperature. And, oddly, the larger the droplets, the higher the temperature at which ice can begin forming in clouds. And when ice forms, snow, then rain, come out the bottom.
To go on too long on this in covering all rain possibilities for yesterday, a base temperature of 7 C here is on the edge of being able to produce droplets big enough so that some begin colliding with one another and sticking together so that drizzle, then raindrops can form, a couple to a few thousand feet above cloud base, and those sizes of drops can really accelerate the formation of ice and then rain out the bottom. Are there any readers left? I doubt it.
Let us go even deeper…. It was hazy, smoky looking yesterday most of the morning, even when some good thunderstorms formed. So what? Well, smoke is bad for storms. Remember when it was reported by Warner and and the U of Arizona’s own Sean Twomey (1967) that sugarcane burning made it stop raining downwind from those fires in Australia? That effect has been verified in satellite measurements by cloud seeding nemesis, Danny Rosenfeld2 of the HUJ in Science a few years ago.
Well, too much smoke can choke droplet sizes down and inhibit the formation of rain by collisions, and delay the formation of ice. And so we had that counter effect of smoke from somewhere, maybe LA this time since it was in the boundary layer, not aloft like that smoke layer from Asia was a couple of weeks ago.
So, cloud microstructurally-spekaing, it was an especially interesting day, one, if he were cloud maven person, wishes he would have had an aircraft to sample them.
But let us look now and see what all the fuss is about:
First, a tedious note about the Big One of two days ago.
While the Davis Vantage Pro 2 tipping bucket gauge registered a whopping 4.18 inches, a smaller plastic gauge from CoCoRahs here had 4.63 inches, after subtracting some rain (half an inch) I forgot to dump due to a brain cramp. A neighbor a couple hundred yards away here in Sutherland Heights, measured 4.65 inches in her gauge, and I now think that the 4.63 inches is the correct amount of rain for this spot. This goes with two other reports of 4.48 inches at Our Garden, and another one of 4.50 inches just a bit on the west side of Lago del Oro Parkway, and the 4.59 inches at the Samaniego Peak ALERT gauge just E of us. We seem to have been in the heaviest band of that storm! (Makes up for all the misses during the summer.)
The Vantage gauge is mounted above the ground, and some loss occurs due to wind, and also when the rain falls too hard, the tipping bucket can’t keep up. The CoCo gauge is ground mounted, and is protected from wind by surrounding natural desert vegetation (aka, “weeds”).
Below, from the University of Arizona’s rainlog.org, is a map of rain totals in our area and the northern areas of TUS. (The Our Garden and Samaniego Peak totals of 4.48 and 4.59 inches, respectively, don’t show up because they are not members of rainlog.org but probably should be so’s we can get all the rain we want to see in one site! I have added those values
In the meantime, from CDO at Wilds Road videos I took in heavy rain as the Sutherland Heights rain started to eclipse 3 inches, this larger wave that formed. I think it could have been surfed.
First of all, it was real disappointing to see so much haze in the air after so much rain! Not sure where it came from yet, will have to do some back trajectories to find out, but later…
The weather ahead
Still pretty confident in more summer rains and tropical air after the current dry spell of a few days, this partly associated with the next tropical storm, likely to be named “Opal” or something like that with an “O” as it takes shape. Of course, we could look up what name it will be, but it will be named soon enough, so why bother?Its already a numbered tropical depression (a weak area of low pressure) down there off Guatemala now.
There are a lot of photos here of yesterday’s clouds, considering it was a day with no rain. Oh, well, pretty normal for a cloud-centric person where the least cloud minutiae is somehow “interesting.”
Next and maybe last rain of the summer (kidding only a little) looks to be around August 3rd still. Flow aloft looking awfully grim overall for summer rain in Catalina mod longer term predictions… This may be the worst thing I have ever said to a desert people during their “wet” season. Let’s hope we have about 5 inches on August 3rd or so!
I wonder if you caught it? Fell between 8:10 and 8:12 AM. Very isolated, and pretty small drops. If you weren’t driving in it, or outside, you would never have known this happened. But observing and reporting events like this is what makes us who we are, you reader of CM. We take pride in seeing and observing what others don’t.
Before the rain hit, some two or three RW– (weather text version of “very light rainshowers”) began to fall to the SW of us from that deck of Stratocumulus clouds. Must have been where the tops were higher than anywhere else. Here’s the first sign, and upwind of Catalina, that you, as a CMJ (cloud maven junior) know to pull your car out of the garage. (BTW, thinking about having a CMJ cookie drive next month…so look around for your best recipes.)
It may seem strange, a non-sequitor, for those blog passersby to be talking about taking your car out of the garage or carport if a slight amount of rain might occur, as was the case yesterday. Here’s the “skinny”, as we used to say in the last century when we were young and could do things: a “clean” car, one that been wiped of all evidence of prior rain drops, but one having a thin coating of dust (you don’t have to apply a thing dust layer, its goes with the territory here) is great as a “trace detector.” And for us, CMs and CMJs, observing a trace such as yesterdays, when ordinary observers miss it (fumble the ball), is like hitting a low outside slider from former Husky pitcher Tim Lincecum, for a game winning touchdown. Or Boise State beating Oklahoma in a bowl game.
Why not just use the radar instead of parking your car outside and if the 24 h depiction of precip shows an echo over you, just mark yourself down as having a “trace”?
That would be cheating! Besides, some echoes seen on radar are only aloft.
And what if you’re in a “data silent” zone, where the radar beam is blocked by terrain, or is too far away? You’re adding unique information with your trace. Sure, nobody around you really cares if you had a trace or not, but, what the HECK.
Did the tops reach -10 C or so to form ice and cause this shower? Nope. Capped out at 0 to -5 C, so almost impossible to have had ice form to cause our sprinkles. Check this sounding from the WY Cowboys, who are off to a good season BTW.
In examining this TUS sounding closely, its good to remember that we are NOT Tucson, but in Catalina. We are 14 miles from the city limits; have a road sign that sez so. “Hey”, we aren’t even on the same side of the mountains as is “Tucson.” In fact, you have to go through the city limits of Oro Valley to get to Catalina! Only the Post Office thinks that Catalina is in “Tucson.” OK, got that in…
And, during the cooler season when troughs go by, as yesterday, the temperature profile from Tucson balloon is not accurate for us here in Catalina; its always that bit colder to the north and west of the balloon launch site for days like yesterday. So, like a chef, adding that bit more of butter or garlic, OUR sounding should be tweaked from the TUS one to show slightly higher and colder cloud tops, probably near – 5 C, not at ZERO or slightly cooler in overshooting Cumulus/Stratocumulus tops as would be expected from the Tucson sounding. Also, since it sprinkled at 8 AM, and not 5 AM, its also likely that clouds tops were going up some as the trough from the west approached yesterday. So there are lots of possibilities.
Sure wish we’d had a PIREP! (Texting form of, “Pilot report”). Any CMJ’s out there have an aircraft that we could take up and kind of poke around up there, see for sure what really happened instead of “hand waving”?
Absent aircraft reports, I am going to say that almost certainly yesterday’s sprinkle was a case of rain formed by “collisions with coalescence, or via the “warm rain” process (called that because it doesn’t have ice), sometimes called here, “coalision” rain. Very unusual in Arizona and, you can see that if you have to park your car outside to see how much came out of a cloud producing rain through “coalision”, it doesn’t amount to much.
You know, this is a great story for you. First, you observe rain that no one else did, or even cares about, until maybe you tell them it was almost certainly caused by collisions among cloud droplets, and then watch their eyes bug out!
Had some spectacular highlights again on the Catalinas, and also evidence of the aerosol loading as we say, in the crepuscular rays (colloq., crepsucular) shown below.
Since there is STILL no rain indicated for the next 15 days in the models, just dry (for now) trough passages, I may have to discuss yesterday’s sprinkle again tomorrow. Thinking of a title even now: “That sprinkle; more insights on what happened.” Yeah, that should do it.
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