Art Rangno – Page 93

Story time: They said they couldn’t exist, but we found some anyway (extra giant raindrops)

While waiting for the chance of rain mid-week next week, I thought I would tell another science story…

How me and Doc Hobbs got into the Guinness Book of World Records

Rain drops bigger than about 5 mm in diameter (only about 0.2 inches) are thought, mainly through lab experiments, to break up into smaller drops before they reach sizes larger than that. Also, they had not been reported to reach sizes larger than that until the mid-1980s when researchers sampling modest Cumulus congestus clouds topping out at only around 14,000 feet around the Hawiaan Islands reported intercepting drops that were 4-8 mm in diameter. This was pretty big news.

Later, while flying with the University of Washington’s research aircraft we intercepted (imaged with aircraft laser probes) drops that were 8.6 mm across and more likely as large as a centimeter, and not on one, but two different occasions separated by a few years. These were larger than the ones reported by the Hawaiian researchers. (Yes!!!! Spiking football now!!!)

First, the award-certificate for those who might be skeptical, and whose display is best part of today’s blog! I mean, really, I could have put 257 worms in my mouth or that sort of tawdry thing, but this was much better, more digestible. Oddly, neither Peter V. Hobbs, my co-author, and I know how we got this Guinness Certificate; it just came in the mail sometime after our article, Super-Large Raindrops appeared in the journal, Geophysical Research Letters in 2004. You know, it wasn’t that great of a “certificate” either. I thought it would be on onion paper, or some other exclusive bond. Instead, it was on something like a cheap, thin cardboard paper. Still…….

The two instances of where these giant drops were encountered were in completely different, contrasting aerosol environments: one in a clean, smog-free, oceanic environment near the equator in the Marshall Islands, and the other under a smoke-filled Cumulus congestus cloud in Rondonia, Brazil, an area where there were many fires where the tropical forest was being burned away. (We were in Brazil 1995 along with other research aircraft to study the nature and extent of the smoke being produced by those awful fires.) Since any rain is thought to be hard to produce in smoky clouds that do not get to the Cumulonimbus stage, giant drops from them was news, too. Of course, many of you out there enjoy photographing images of raindrop splatters on various surfaces as kind of a hobby, particularly as rain begins to fall. Below, is an example from a friend of that sort who prefers to photograph those splatters as they occur on cement as an artform. I think her work is in a local gallery…

So, knowing how much general interest there is out there in rain for desert dwellers, which still might occur on Wednesday or Thursday, is the reason for today’s blog on huge raindrops.

Below is an example of what rain drops look like when they imaged by laser probes on the University of Washington’s research aircraft as we flew through those two instances of giant raindrops. The images of the drops are the shadows of them. As they pass under the wing of the aircraft, some go through a laser beam without being disturbed. The laser shines on photosensitive diodes that get turned off and recorded when they are shadowed. They stay off until the laser beam hits them again, thus recording the dimensions of whatever it was has passed by. You then look at the diodes that were turned off for the tiny fraction of a second that something went through (for our aircraft, around 100 to 120 mph) and get an image of it that tells you whether it was a drop, ice crystal, snowflake, graupel, whatever. Pretty amazing when you think about it. You’ll have to click on it to really see anything.

The large red drops on the left side in the bottom rows are the partial images of the record setting drops. The probe elements were not wide enough to see the whole drop. On the right side is an ellipse fitting routine applied to the raindrop images we recorded that better displays the true size of partially viewed drops. In this case, that algorithm suggested the very largest were about 1 cm (you can use that as a scale for the other ones), but because it is an estimate, does not count in the record books. Only the actual measurized size was considered in the Guinness record. The top two panels are from the Brazil encounter, and the bottom two panels are from the one near Kwajalein Atoll, Marshall Islands.

Here are some photos of the two areas we flew in so that you can see how different they were in character. First, Kwajalein Atoll (note the gigantic runway, constructed in WWII, had its own cloud on calm days !). Second, an example of a moderate-sized Cumulonimbus cloud, one similar in size or even a bit larger than the one Mr. Cloud-maven person himself was directing the University of Washington’s Convair-580 research aircraft into, targeting the heavier strands of rain that first falls from convective clouds. It was so GORGEOUS there in Kwajalein! I loved it there. The skies, the sunsets! Oh, my.

Kwajalein Atoll, BTW, is the terminus of the Vandenberg missle launches. As yet another aside, on the TEEVEE there in Kwajalein, there were announcements in big red letters, like the ones for severe weather, that told you when a missle had been launched at Kwakalein from Vandenberg, and when it was coming into the middle of the Atoll (you hoped!) Folks would then gather on one of the Atoll beaches to watch the show. It was so exciting!

As an aside, I have to tell you that one of the charms of that place, run by Raytheon, a name you are familiar with around here, was that you could not own a car, or house, or just about anything else, paid no taxes if you were a permanent employee, etc. You had to have a bicycle for transportation for the most part. It was like the atmosphere of a small (“communist”, hahaha) town (3500 lived and worked there). Everyone went outside and walked or rode down the streets in the evenings. Another charm was that the manager of the Kwajalein Missile Range site had hair down to his waist! It was AMAZING! Both he and his wife seemed to be in their late 30s with two little kids, and told me how much they loved it there! Many others did, too.

Now on to the smoky environment in the State of Rodonia, Brazil, 1995, in the “dry season”, where the other giant drops were encountered. Rodonia, at that time of year and in those days, was a pyromaniacs paradise.

First, the University of Washington’s research aircraft sitting on the runway in Porto Velho, Rodonia, Brazil. By clicking on this image, and looking under the wing on the left, you can see the “Y” shaped probe that imaged the giant drops as they flew by. Other images show the “Green Ocean” in smoke, and some ground shots that show how widespread fire was there. In fact, after a couple of months there, we kind of got “into the culture” and wanted to burn some things up ourselves. Check the fire along the highways! No “Fire Danger is High” signs there! I think its time to reprise Deep Purple’s “Smoke on the Water” (which is just about everywhere else in Brazil, anyway) to get you in the mood for the shots to follow. I will be jumping around now… (Too bad Beethoven couldn’t write songs as good as this, but then he wasn’t that great with words….) The last shot is a sunny day in Cuiaba, a large interior city of Brazil, during the burn season.

As an epilogue it should be pointed out that Brazil is making good progress in controlling the amount of burning compared to that which was going on in 1995.

Below is the region of “pyrocumulus congestus clouds (those due to fires below them) where the giant drops were encountered, near the city of Maraba, Brazil. It was a little different than Kwaj!

The End (at last)

Smoke and mirrors in the models; fire in the sky

For those of you who have forgotten that heavy metal pioneering band, Deep Purple, and their hit, “Smoke on the Water”, to which this post sort of alludes to, straining really, take this. It was kind of fun to see this “songumentary”, because it was about something that really happened. In a line out of Spinal Tap, the parody heavy metal band, one review considered Deep Purple, “the globe’s loudest band.” How funny!

Here’s the “fire in the sky” at sunrise yesterday, and in case you missed it. Fabulous blaze of fire underlighting those Altostrastus clouds with their snow virga.

Then, in the afternoon, we had these sky gems; Altocumulus clouds, mostly of the floccus and castellanus varieties, some shedding ice in what up there would have felt like snow flurries. For those three of you who follow this page, you can guess immediately how cold those ice-shedding Altocumulus clouds were: colder than -10 C, and probably colder than -15 C without even looking at a temperature sounding.

The weather ahead; discouraging.

The models have been gradually reducing the chances of rain since the last blog about rain ahead, and when they do show rain on or around February 7th, its been reduced from what was once going to be a substantial period of rain to a minor event. Hence, the models have truly come up with “smoke and mirrors”; looks real but its not.

Rain “puddles” still on model highway

..like the continuing puddles of water we see on a hot day in the distance on the road. So, in the model outputs of late, there have been a couple of rainy “puddles” for southern Arizona on the horizon, 10 days out and more. Still too far out to be reliable; they might “dry up”, as our highway puddles appear to do.

But, I would have slept in if I hadn’t been “provoked” into a blogulent life this morning by CONTINUING RAIN in the model forecasts for southern AZ. Here are the key elements from last evening’s new results: It still rains on February 12th, though the amounts have been scaled back; not the deluge suggested yesterday. However, a soaking rain is now indicated for February 6th, a week earlier from an entirely different system (!), previously shown as a near miss or a mere wisp of rain.

Its all good, because a pattern change is taking place, and while the details and timing of rain will be erratic for awhile, its likely that the pattern change to one that provides rain here is more likely, not “in the bag”, of course, by any means.

What would be great about a February wet spell is not only the effect it will have on our spring growth and sustaining the road to a good wildflower bloom, but also just to see decent rain in the heart of the La Nina rain deflector period. As you likely know, the power of a La Nina to deflect storms from the Southwest is greatest in late winter and spring. Rooting for rain now into spring is definitely like rooting for a 20 point underdog in fubball.

Here are some images from last night’s model output, rendered by IPS Meteostar, my favorite for these. The first for Monday, February 6th, “bulls eye”, and the second for the February 12th storm. Contrast the flow shown on the jet stream maps (panels 3 and 4) with what we have today (last panel) to see why we weather folk call it a pattern change. Look where the jet stream crosses the coast these days and where it is on the rainy forecast days ahead.

As you can see, by the 12th, Cal will also feel the impact of another round of furious weather after the January lashings that brought 10-20 inches of rain to extreme northern portions of the State and in southern Oregon. The largest total I have found from the later January deluges was….33.56 inches in just NINE days at Red M0und, Oregon, just north of Brookings! Time to start thinking about another trip to Shelter Cove, CA, and the King Range. Hmmm. Just kidding! I would not willingly miss a drop of rain that falls here, just too beautiful a site to see rain fall in the desert. We love rain here!

The End.

Factoid: If you are a snow birder from Prospect Creek, Alaska, about 180 miles north of Fairbanks, I am quite sure you are happy to be here and not there; the temperature yesterday morning at Prospect Creek was -77 F! The US record low temperature is -80 F set at Prospect Creek in 1971. Must be like living in liquid nitrogen there in the winter.

Rain at the end of the tunnel?

Finally, the dark tunnel of pleasant, dry weather may be coming to an end, I am happy to say. The WRF-GOOFUS model longer range output has been showing RAIN in southern Arizona for two or three runs out around the 7th to 14th of February. Of course, those who follow this blog know that RAIN predicted in southern Arizona that far away is like the square root of -1. It doesn’t really exist; its imaginary. Still, it COULD happen, and you get a little more confidence when it shows up in more than one model run. The USA! WRF-GFS model is really very good out to about five-seven days, but gets “goofus” after that, you almost always can’t rely on what it says with rare exceptions. But, that having been said, remember that our models are still a lot better than economic forecasting models. Think of the unforeseen “black” stock market days that come up! Q. E. D. They don’t know what the HELL they are doing over there. Just kidding.

Below, some happy thoughts should accrue from viewing the images below if not already in place due to coffee. Think of flowers. And, if you’re like me, you’re happier overall and feel better about yourself thinking about a future rain in a desert region. Below, what the WRF-GOOFUS model thinks February 12th will look like, based on thinking done on last evening’s (5 PM AST) global data. This is so good I have reproduced TWO renderings from IPS Meteostar for that day. It can hardly get ‘”greener” (show more precip) in the entire Southwest than what this storm is supposed to do on February 12th, and we even see some dark “green” (heavier rain), turning into blue (even heavier rain) in southern Arizona in this sequence. Streams would likely run in places in southern AZ with this overall scenario. Its a great thought!

BTW, the later model run, just six hours after this one (based on 11 PM AST data, but whose awake then to take good obs and there aren’t that many anyway?) took a lot of this rain away and so I didn’t want to show it because its who I am. (hahahaha, sort of)

On a more mundane level, another fabulous AZ sunset last evening caused by…..what kind of clouds am I? Moslty Altostratus (really thick all or mostly ice clouds) and Altocumulus (mostly droplet clouds far horizon and very thin). See far below.

The End.

Pomp and circumstance, but only a hundredth

“Pomp”, in the form of some thunder and lightning, and a few hail stones between 10 and 10:30 PM AST; “circumstance” with a pretty strong trough going by. But they only delivered a hundredth of an inch of rain at the ground here in Catalina. I guess the bugs will be satisfied, but it was a tiny bit disappointing to me. Was hoping for TWO hundredths. The U of AZ computer model did a nice job foretelling a tenth or less of rain. The most rain reported around here is 0.12 inches way up in the Catalina Mountains at CDO and Coronado Camp.

In case you missed it, here’s when and where the lightning occurred from Strikestar-Astrogenic systems. The last panel, lower left, shows those surprise lightning strikes that occurred around 10:15 to 10:30 PM AST last night. BTW, these folks have the best presentation of lightning occurrences that I have been able to find, one that includes non-ground strikes.

Now its sit and wait in the sun for maybe two weeks or more for precip. The closest thing to a storm here in the next FIFTEEN days that the models (courtesy of IPS Meteostar) are showing is this very strong upper low and trough that, as shown below over the Four Corners area, passes by too far to the east of us on February 1st-2nd to be considered a threat.

This system been showing up on the models for days and days, sometimes as one that can bring rain here, but it hasn’t been shown that way lately in the models. The fact that it has been persistent as a feature that affects the Southwest is a good sign that something major will pass by us in early February, and at the least will bring quite a chill whether we get precip or not.

In the meantime, we will have to be content with a long, long stretch of a sunny weather malaise, where almost everyday is perfect for a winter day.

Clouds?

Here are some from yesterday, and again, a great, late-blooming sunset. Almost gave up on it happening. First, the nice strand of Cirrus yesterday morning that heralded the thicker layers behind it and shots of those multi-layered clouds consisting of Altocumulus, Altostratus (the smooth one), and then the sunset “bloom.”

The End.

“And I think its going to rain today”

Well, how can we forget that mournful Leonard Cohen song? And the sweet rendition of that tune by Judy Collins? It was played a lot in Seattle, of course, where I’m from. But, it also looks like it might be apt for late today right here in Catalina. Check out this “incoming” here from the U of AZ Weather Department’s model output here. This loop of rain areas will show you how the precip creeps toward us during the day, eventually overrunning almost the whole State of AZ. “Oh happy day”, to quote another song title. Just hope we get more than the tenth of an inch the model projects, all of which falls overnight tonight after midnight. (Hmmmm. Seems a little slow to me.)

Here’s a loop of satellite imagery and the surface pressure maps for the past 24 h from the University of Washington. The interesting thing about these maps, is how one hurricane-like center with lots of isobars off the Pacific NW coast crashes into British Columbia while a new low develops off the California coast and is now pummeling central and southern California while heading to the southeast and toward us. Reminds me of someone getting a “spare” in bowling by knocking two widely separated pins to the left and right to get it.

Why would storms divide in their paths like that? You have to look aloft at the steering by the jet stream. Low centers separating like that always means there is a split, a dividing point in the flow. Higher level pressure maps from the UW shows that. Below is a 300 millibar pressure map (about 9 km above sea level or around 30,000 feet), a level where the jet stream is just about the best developed. Notice how part of the flow whirls around the big vortex in the northern Gulf of Alaska and toward BC, while a more powerful branch dips toward California. Its that trough, that bend in the winds just now off California, that will come barreling through here tonight bringing that surface low center now near SFO with it–well, what’s left of it after it gets wrecked by mountains. The next chance for rain/snow is in early February.

Nice clouds again yesterday. Here are a few shots, including another nice sunset. The haze you saw was dust, leftover from the strong winds of the previous day in western AZ. The first, Cirrus over dust. The second, some Altocumulus with Cirrus, and finally, Altostratus with some under lit Altocumulus in the distance.

Near miss on rain; pretty clouds and a nice sunset

Here are a couple of scenes from pretty yesterday, a day that the phony numerical models had rain predicted for us one to two weeks in advance, and then dried that system out as far as we here in Catalina are concerned as the days got closer. This happens all the time in the models, so you would think I would develop a tough skin to these repeated disappointments, but I haven’t. Oh, photos. Here they are-the middle panel having a nice pancake-like stack of Altocumulus lenticularis clouds northeast of Charouleau Gap:

So what was the missing ingredient? Well, the core of the jet stream at around 18,000 feet above sea level, what we call the 500 millibar pressure level as well, stayed just to the north of us. If you have read this blog, you know that the core at 500 mb has to be over or to the south of us and that didn’t happen. Its a necessary condition in the cool season here, but not always sufficient. Shown below is last evening’s 500 mb map, courtesy of the University of Washington with station plots and infrared satellite imagery. Those two flags and a wind barb for our Flagstaff balloon site (“rawinsonde” site) shows that the core of the jet stream was just about right over Flagstaff at that time, and the wind was over 120 mph (105 knots)! Note that the wind at the same pressure height on this map is “only” 65 knots over Tucson. By this morning, that core had settled a little more southward to between Albuquerquequeque and El Paso, and along with that the precip shifted a bit south as well. Darn, had this happened 12 h earlier we likely would have gotten a small amount of rain.

If you look at a loop of the radar echoes during the late afternoon and overnight from IPS Meteostar, you will see that the precip is confined to near that jet stream location and northward.

Shown on the Washington Huskies loop is another powerful storm about to strike the West Coast. THIS one WILL bring the jet stream core south of us as it passes over on Monday night-Tuesday morning, the 23rd-24th, and circumscribed inside that jet stream core will be moisture and clouds low enough to produce at least scattered showers, and may a nice rain band of a few hours duration. So, maybe the rest of January won’t end up as rainless after all.

The best thing about this next trough is that it gets stuck as a cut off over west Texas and causes quite a bit of rain there in that drought stricken region for a couple of days. Might have to drive over there and see how happy the people of west and central Texas are when the rains begin.

Don’t want to end this session without a long distance model teaser, “big storm” from IPS METEOSTAR as shown here valid on February 3rd at 5 PM AST. Note how it resembles once again our early winter pattern of the isolated cut off upper low. Hmmmm. Maybe there will be something to this one because of this winter’s theme song of cut offs.

The End.

Looking ahead to February…to keep rain in the Catalina future

Forgetting about that rain foretold in the models sometime in a January 21st-23rd window there for awhile, there might be a big storm at the start of February!

Trying to distract you from that earlier though of rain in just a few days because now the models think the core of the jet stream and rain/precip with it will only affect the northern portions of the State of AZ. The last few runs have been COMPLETELY dry here and so going into a funk.

But, “hay”, look below at this dreamy (read, probably “unreliable”) output for February 1st at 11 PM LST (whole sequence here, click on 06 Z run time)!

Oh, well, its the best I can do to talk about rain/snow in Catalina now. Sometimes its tough being a precipomaniac in a desert.

Clouds? With the jet streaming near us, but to the north, we should see lots of nice cirrus-ee sunsets and sunrises from time to time over the next few days. That will help any funk.

The End.

A Stratocumulus Monday

Yesterday gave us “Catalonians” the perfect example of Stratocumulus clouds. But why didn’t it rain from those dark clouds, save a few drops, maybe even a brief drizzle episode that mostly moved across Saddlebrooke around 9 AM?

Those Stratocumulus clouds were GENERALLY not cold enough at cloud top to have ice crystals form in them. There were some very light showers, mostly east of us during the day, and THOSE clouds got cold enough at cloud top to have ice form in them.

How cold does a cloud top need to be in Arizona for ice to form in it?

Around 15 F (-10 C).

Here’s the TUS 5 AM AST sounding for yesterday from the Weather Cowboys at the University of Wyoming showing the tops are right around that (normal) ice-forming limit. Where the lines split apart is close to where the cloud tops are, and the temperature lines slant downward to the left.

You may have also noticed that the clouds got markedly shallower here after about 3 PM, noticeable in the U of A movie after 3:30 PM AST. That was also close to the time an upper level trough and the accompanying slight wind shift occurred. To the rear of the trough, there is always a piston of downward moving, drier air that’s going to squash cloud tops. By the evening TUS sounding, cloud tops were barely below freezing.

Some cloud shots from yesterday’s overcast:

SONY DSC — Sharp-eye folks will detect a sprinkle over Charouleau Gap

The weather ahead

Still looking for rain here on the 22-23rd, HOWEVER, the last two model runs confined the rain to N of us! Not good.

Nor Cal rains/flooding episode begins overnight as a series of semi-tropical storms strike the coast.

Wish I could be there for surf and on the turf there, but I have my blog audience to think about. I don’t want to let both of them down by being gone for the 10 days of this great storm series, exploring the rain intensities in the coastal ranges of Cal. Oh, well.

Still think total rains in the best coastal mountain spots over the next ten days will be 30 inches or more, actually not terribly unusual in the King Range and similarly exposed sites.

Twice as nice; 0.53 inches in Catalina (0.58 inches as of 6:39 AM AST)

What a superb rain that was last night. It just kept coming until finally we piled up an astounding-to-me 0.53 inches by 4 AM this morning. The regional rain reports from around Tucson can be found here. As you will see, the upper regions of the Catalina Mountains got around an inch (1.22 inches at CDO wash at Coronado Camp now). Mt. Lemmon probably got a little more, but the record says “0.00” due to snow at that elevation. This is a substantial boost for our emerging spring desert vegetation after our four week drought. This is so much better than that near rainless January of last year! Looking at some of the statewide precip reports, it looks like the Catalina area and the Cat Mountains got more than anywhere else. Lucky us.

If you would like to relive yesterday, at least in clouds, go here to the U of AZ time lapse. One of the things you will see later in the day are Altocumulus lenticularis clouds over the Catalinas. You will see their upwind edges spurt upwind (seem to go the “wrong way”, against the wind) as the lifted air got more moist, one of the tricks that these clouds can pull. You will see quite a panoply of clouds in this movie, from Stratocumulus, Altocumulus, Altostratus (dead gray and smooth higher layer), Nimbostratus (when the rains come) along with some mammatus formations. Hmmmph. There’s that “m-word” again, the one I used so many times yesterday. Wonder what’s going on?

“But wait, there’s more!”

If you call now (well, actually if you continue reading) you’ll find that a few more hundredths of rain are possible this morning before about 8 AM AST, AND, (We interrupt this blog for an important message: “hey”, just started raining again now at 5:03 AM! Yay!)

all of the model runs are indicating rain again on the 22-23rd timeframe; even the “pernicious” 00 Z run from the 5 PM AST global data. (I have questioned that output of late, rationally or irrationally, because it kept drying the State of Arizona out whilst the model runs before and after that time, foresaw precip in spades in the State.

Here is a sample of the IPS Meteostar renderings of what happens in our rain window of the 22-23rd according to our latest model run, one from 11 PM AST data. Note green areas of precip in the 6 h ending at 5 AM AST, Jan 23rd. This is pretty satisfying since another good rain will keep us on track for a great spring bloom.

On other fronts…

While I could go on to talk about all sorts of things due to the ambiguity of the subtitle phrasing above, I will actually only talk about weather fronts, not this or that.

The coming floods in northern Cal-Oregon still on track. Storms break through from the Pacific “under” the Bering Sea “blocking” high, one that diverts the potent Asian jet stream that comes into the Pacific into two branches, one of which is forced southeastward in the central Pacific where water temperatures are warm. (Just heard some rain on the roof again. What a nice sound that is!) The other branch goes deep into the Arctic and merges with the southern branch in the eastern Pacific after it turns southward over AK.

Those warmer storms, heavy with semi-tropical rain clouds, race to the West Coast once the southern jet breaks through the weakening southern part of the blocking high. And once that jet stream has broken through, its days before things change, so the duration of rain adds to the colossal totals certain to occur now. In a ten day span, beginning tomorrow, the peak totals in this event will likely exceed 30 inches of rain.

Here is the current weather map (5 AM AST today) from the University of Washington that illustrates the odd flow pattern developing now from the central Pacific to the western US. The block is developing from a ridge in the eastern Pacific now (evidenced by the lack of green contours in it) that extends from the tropics all the way to the Bering Sea! It will fracture in its southern portion tomorrow. It has overextended its “reach”, in a manner of speaking, at this point, and will fail just like a dam break and all those clouds to the west of it will flood eastward. Its a pretty exciting thing for us precipophiles.

Canadian behemoth

One particularly bruising storm, one the size of Asia practically, with “tentacles” from the Aleutian Islands to Minnesota, was shown to develop in this series of storms battering the West Coast in the European model run by Environment Canada based on last night’s data.

I show this output below because you RARELY see a low whose circulation is this big, at least one of the biggest I have ever seen, portrayed on a weather map (upper right panel). The map below showing this colossal low is valid for the evening of Jan. 21st. The entire West Coast would be battered by this bruiser.

The End.