Surf along the Baja coast, that is, and dewpoints here. Whopping 67 F in TUS, 73 F in Nogales right now. Cat 3 Hurricane Norbert’s is creeping up the Baja coast as of this hour with SUSTAINED winds of 120 mph, pretty far north for that kind of intensity.
Norbert’s peripheral circulation is working its way into Arizona at last. Things aren’t so great upstairs on top of that moisture coming in down low, and so we can’t expect a LOT of showers around today, but more than yesterday, which was almost none. Things gradually improve up top tomorrow and the next day, and so more grouping of showers is expected. Norbert is still forecast by the USA! WRF-GFS model to pass over San Diego on its way across northern Arizona. It will go from a “lion” to a little kitty” by the time it reaches SAN and then it will be just a muddle of clouds trekking across northern Arizona after that.
The important thing about Norbert is the drought-relieving rains it will bring to much of the Southwest. Norbert and its remains will affect Arizona for a few days, then nothin’ after that. So, hoping we can get a few inches of rain out of this situation somewhere in Arizona before it clears out during the middle of next week.
Yesterday’s clouds
10:22 AM. Got really excited when I saw this happen, that extruding top from the raggedy Andy mass below! What a great sign for a few good Cumulonimbi, but not too many since it had dried out overnight!
12:01 PM. Cumulus congestus clouds continued to mass on top of Ms. Lemmon, but the expected explosion into a big Cumulonimbus had not yet occurred, somewhat surprisingly.
12:19 PM. First ice! Can you find it? Looks like things are beginning to boil now, big Cb moments away, (“Not”, as it turned out.) 1:05 PM. Another good sign was Cumulus congestus building over there toward Saddlebrooke Ranch and the valley areas. Looked like they, too, were ready to group and explode. Such a pretty scene.
1:32 PM. Things are getting “muddled.” Instead of nice firm cloud bases, we have kind of a mess. No Cumulus eruption is going to come out of this. At this time, you and me were just looking around to see if any tops had gotten cold enough to form some ice for at least a light rain shower on the mountains. Didn’t see any here.
6:08 PM. While some heavy Cumulus and a couple of Cumulonimbus clouds were sighted well to the SW of us, the clouds here withered as it got drier during the day. You see, even though it was moist below, when Cumulus turrets begin shooting up, there must be (gradually) subsiding air to take the place of the air that shot upwards. So, the extremely dry air just above the tops of our Cumulus was sinking down and dessicating the air from which the Cumulus arose from. Oh, well. More moist up top today….. Won’t be quite so bad in helping to eradicate our Cu.6:45 PM. Cirrus spissatus cumulonimbogenitus (there’s a mouthful!) makes for a pretty sunset, as do those distant Cumulus towers as Norbert’s moisture begins to show up aloft.
Thank you, second burst of rain after about 8:15 PM. And what a great total on The Lemmon! Fantastic, unless some roads were washed out. 1.93 inches fell in only an hour up there. 1.85 inches fell in an hour at White Tail over there by the highway.
Catalina Area 1010 0.00 0.00 0.00 0.00 0.28 Golder Ranch Horseshoe Bend Rd in Saddlebrooke 1020 0.00 0.00 0.00 0.00 0.28 Oracle Ranger Stati approximately 0.5 mi SW of Oracle 1040 0.00 0.00 0.00 0.00 0.43 Dodge Tank Edwin Rd 1.3 mi E of Lago Del Oro Parkway 1050 0.00 0.00 0.00 0.00 0.43 Cherry Spring approximately 1.5 mi W of Charouleau Gap 1060 0.00 0.00 0.00 0.00 0.55 Pig Spring approximately 1.1 mi NE of Charouleau Gap 1070 0.00 0.00 0.00 0.04 0.87 Cargodera Canyon NE corner of Catalina State Park 1080 0.00 0.00 0.00 0.00 0.24 CDO @ Rancho Solano Cañada Del Oro Wash NE of Saddlebrooke 1100 0.00 0.00 0.00 0.00 0.51 CDO @ Golder Rd Cañada Del Oro Wash at Golder Ranch Rd
Santa Catalina Mountains 1030 0.00 0.00 0.00 0.00 0.75 Oracle Ridge Oracle Ridge, approximately 1.5 mi N of Rice Peak 1090 0.00 0.00 0.00 0.04 3.07 Mt. Lemmon Mount Lemmon 1110 0.00 0.00 0.00 0.00 0.63 CDO @ Coronado Camp Cañada Del Oro Wash 0.3 mi S of Coronado Camp 1130 0.00 0.00 0.00 0.00 1.69 Samaniego Peak Samaniego Peak on Samaniego Ridge 1140 0.00 0.00 0.00 0.00 0.94 Dan Saddle Dan Saddle on Oracle Ridge 2150 0.00 0.00 0.00 0.04 2.72 White Tail Catalina Hwy 0.8 mi W of Palisade Ranger Station 2280 0.00 0.00 0.00 0.00 0.59 Green Mountain Green Mountain 2290 0.00 0.00 0.00 0.00 1.18 Marshall Gulch Sabino Creek 0.6 mi SSE of Marshall Gulch
Looks like scattered showers today; a typical sequence after something major happens, like last night, is for the atmosphere to compensate with some drier air. So, today should be GORGEOUS in Cumulus clouds that pile up here and there on the mountains, but don’t expect to get shafted unless you’re real lucky. Wider spread rains expected tomorrow….
Yesterday’s clouds, if you care
Of course, you can the whole day in a hurry here, courtesy of the U of Arizona Wildcats Weather Department, in case you’d like to avoid all the cloud blather below….
6:20 AM. I/m calling this Altocumulus. Don’t see any ice falling out here, but some did off to the SW. Being an all water droplet cloud, I hope you were telling anyone that you were with, that, “Hell, this layer will burn off fast” since you know that water droplet clouds are more vulnerable to evaporating in sunlight than ice clouds like Altostratus, or Cirrus. And when this layer burns off fast, the Cumulus will arise in a hurry. Its great that you might have said that.9:13 AM. That layer is mostly gone, and there come the Cu!1:03 PM. The inevitable Cumulonimbus capillatus incus has arisen over there by Kitt Peak. But this photo is special for you because if you look closely, as I know you will, there is also a big dust devil near the Tucson Mountains (center of photo). I’ve noticed a LOT of dust devils form in nearly that same spot where this one is. Must be exciting to live down there!1:30 PM. Another daily benchmark, “First Ice” on the Catalinas. The ragged turret remains on the left have some ice underneath them if you look closely again, as I know you probably will. If you had an aircraft with cloud physics instrumentation and you were looking for the amount ice that formed in those ragged turrets, ones that once looked like the one in the center, nice and puffy, you would best fly toward the bottom of the rags, not at the top since as the droplets in the cloud shrink due to evaporation, the ice-forming stops. Thus sometimes the coldest part of the cloud in those rags has the fewest ice crystals, and more are found lower down, ones that formed by the freezing of those once larger drops, as would be starting to take place in the puffy parts.3:56 PM. The rarely seen pileus cap which I seem to photograph everyday on a Catalina mountain Cumulus congestus cloud top. Very pretty, and SO DELICATE! Things had kind of stagnated as far as Cumulus development went at this point over the Catalinas. Lots of small Cbs, but nothing really shot up, as it was beginning to do to the southwest and west.4:15 PM. Another rarely seen pileus top on a Cumulus congestus converting into a Cumulonimbus calvus; ice in a fading, glaciated turret is visible on the left (that smooth portion). Still, these tops ain’t much in height.5:57 PM. Now the big boys to the SW are approaching with huge “plumes” of Altostratus cumulonimbogenitus–you knew that, though in fading versions it appeared. Note dust plume on the right obscuring part of the Tortolita Mountains. And with their approach, and with the dust plume over there, you could easily figure that the wind was gonna blow pretty hard.6:00 PM. Only four minutes later, the dust was moving in and the wind was blowing from the SW at 25 to 35 mph. When the wind starts up, look up! That wind will be pushing the air over you up, and often existing darken as their tops rise, or new clouds form. Here, and in the next shot, that SW wind is pushing the air up on the slopes of the Catalina Mountains. Was hoping to see the strands start to fall from these bases near us, maybe feel some “rain plops” as we call them, those giant drops first out the bottom, but that didn’t happen here, but over there on Ms. Lemmon and Samaniego Ridge after that. Oh, well.6:06 PM. Another example of the clouds that piled up on the Catalinas as that SW wind was blowing. Wasn’t long after this that Ms. Lemmon was obscured in rain.
Our last cloud chapter was rudely interrupted by drought, with the last “rain”, an embarrassing one, of just 0.01 inches here in Sutherland Heights a week ago. Areas around us, of course, got more.
6:40 AM. “Etched glass” Cirrus fibratus. The flocculent patches (center right) are newly formed ones in which the larger ice crystals that are falling out of the stranded regions, have not yet gotten big enough to fall out, but they will follow that same course.
7:08 AM. CIrrus fibratus/uncinus radiatus, or at least the perspective makes it LOOK like its converging in the upwind direction. Had to pull off for this shot, it was SO NICE!1:32 PM. Surprise of the day was seeing real Cumulus (mediocris) clouds forming over our Catalina Mountains underneath patchy Cirrus and Altocumulus clouds. Note the rarely seen pileus cap cloud, indicating a good updraft.1:32 PM. Close up of the rarely seen pileus cap cloud. Would really like to have been in it, and then feel the bump when the Cu top rises through it!2:04 PM. Nice to see some unexpected shafting around, even if they were weak, indicating the tops were not terrifically high. With bases at the freezing level yesterday (14 kft above sea level), ice would not form until lower than normal temperatures, maybe around -15 C (5 F), but then would increase with each lower temperature. Here guessing were likely around -25 C, 25,000 feet or so above sea level due to the weakness of the shaft. Got a higher later. Very iffy discussion here, but that’s what CMP thinks.4:31 PM. Evening closed out with R— (“triple minus”–hardly noticeable RAIN not drizzle, please) from mid-level clouds, Altocumulus being the lower, lumpy gray patches, and Altostratus Cumulonimbogenitus, being the one producing the sprinkles, not drizzle.
Today’s weather….
Well, its no fun telling folks what they already know, but will say it looks tentatively, relying on the U of AZ 11 PM AST run of last night, like a day similar to yesterday, except a cloudier morning, which I just saw was the case by looking outside right now at 5:49 AM. Cu develop, tops should get cold enough to produce ice-hence-rain and shafting. Hope its measurable today. Also, as you know, moisture levels increase over the next couple of days with substantial rains likely.
In a model curiosity, three consecutive runs of the US WRF-GFS model, beginning with the 5 AM AST, 11 AM AST, and 5 PM AST runs, all from yesterday, had the remains of tropical storm Norbert passing directly over San Diego with substantial rains there. What made it even more likely to happen was that the Canadian model run from yesterday’s 5 PM AST global data, ALSO had the remaining little center of Norbert passing over San Diego, Tuesday, September 9th! Amazing since Norbert is such a tiny feature in our models, at least by the time it gets near San Diego.
As reported here, a month or so ago, the newly discovered oscillation in ocean temperatures, called the “California Niño”, is helping to keep Norbert going longer as it trudges to the NNW just off the Baja coast. Water temperatures off Cal are warmer than usual this summer due to weak onshore flow for the past few months. When the flow is normal, it not only sculpts plants and trees along the Cal coast, but also causes upwelling of COLD water, horrible for beach goers.
Below, examples of wind sculpting1:
Bodega Bay, CA, just north of Frisco, that windy, foggy, “Stratus-ee”, and cold summer city. Note Stratus in the background hwew.rolling in off the cold offshore waters. No summer thunderstorms here! Imagine how awful it would be to live at this spot. Winters are pretty nice, though, often with frequent rains and wind….to balance things out some.
Also near Bodega Bay.
The End.
———————————— 1When a realtor shows you property with scenes like these around it, you don’t want to buy there, even if its not windy that day. If you’re a realtor, you’d want to have bushes and trees like this trimmed up real good. hahaha.
Those models have been titillating Arizonans with lots of rain in the coming days, but unlike most prize-winning1 meteorologists, I am going to only show you those with the most rain, rather than those in which the rain is skimpy, not impressive, like the latest model run from last night.
This is because I want you to start your day in a good mood, not a bad one. The summer-style rains in the area don’t return until about Thursday, but you probably already know that from TEEVEE weatherpersons2. Then those rains go on for a few days.
Here’s the BEST of the model predictions, well, two of them, from IPS MeteoStar, whose renditions of the US WRF-GOOFUS model I favor.
Now the first one is a model prediction that’s a couple of days old, the second two are only about 24 h old, having originated with yesterday’s 11 AM global data! The last two have rains of two inches in 12 h predicted in AZ, one center of that rain is just about over Sutherlands Heights/Catalina! Pretty excited and am glad I could find it for you.
Valid Monday night at 11 PM AST, September 8th. Well, it may not be “valid” anymore, but this is about as large an area of rain moving into Arizona as you will find in a model output, so its pretty great to savor. Valid Sunday night at 11 PM, September 7th from a later model run. Note the purple spot on Mt. Lemmon, indicating about 2 inches of rain in 12 h. Tropical low sits off Baja, and spurts NE into AZ after this map. Valid at 11 AM, September 10th. That tropical storm remnant is now over Arizona producing a lot of rain, though the major portion is just west of us.
Now those last two panels of rain are due to a strange situation. A tropical storm brings a surge of showers into Arizona as it passes off Baja heading for death in the cold waters to the NW. But then it stalls, goes in circles for awhile, and comes shooting up into Arizona bring the rain shown in the last panel! So, we get TWO rains from the same storm!
What are the chances this strange storm track will actually happen? Virtually none. But “virtually” none is not all NONE, to paraphrase a memorable line in Princess Bride, so there IS hope that major September rains WILL occur in Catalina/Sutherland Heights in the 10 days ahead. I’m counting on it. Waxing rain gauge now so that drops slip easily down the funnel and into the smaller measuring tube. Be sure to at least wipe the dust off the larger collecting funnel before these major rains hit so that “no drop is left behind”, again paraphrasing something I heard somewhere.
Expecting 1-2 inches during the 7 days beginning this Thursday, with outside chances of it being even MORE. I love predicting a lot of rain for a desert, so you’ll have to take that into account. If you’re upset at this disclosure, being kind of crybaby, and want really good “objective” forecasting with great graphics, then go to Bob M or the NWS! To HELL with you!
The End.
———————————
1It was a consolation prize in cloud seeding studies3, i.e., not that great, that we (Peter Hobbs and I got) like winning the main prize would be. Kind of fits in with my athletic “prizes”; all second team this, all second team that, honorable mention this, etc.
2Some of these “weatherpersons” have not been well trained, and have been “on air”
(!) referring to sprinkles of rain as “drizzle.” Unbelievable. No university-trained meteorologist would make such an ignominious error, unless of course, they skipped classes in cloud microphysics.
3My role in getting that prize was due to finding fault in the work of others rather than contributing solutions to problems.
Like you, I did not expect to see ice-in-clouds yesterday. I could feel your surprise when I looked to the north and saw traces of it in the exhaling part of a Cumulus congestus–like you, really didn’t think I’d see clouds that large, either. But there the ice was.
Later, it was even more obvious, and a fat cell even developed up there toward Globe in mid-afternoon. Didn’t expect to see one so close.
Also, did you catch the cluster of Cumulonimbi on the north horizon at sunrise? That was an unexpected sight for you and me as well.
I wonder, too, if you were down at Steam Pump and Oracle you noticed that a few drops of rain fell? That was really unbelievable, since it was practically clear overhead when I exited the PF gym and saw them on the car I had just washed and waxed in the belief that no rain could fall for at least 10 days. Yes, it was a day of surprises for both of us.
Didn’t think I’d be bloggin’ today, either. Life has so many unexpected twists and turns.
Yesterday’s clouds
6:05 AM. Unexpected sighting number 1: Dawn Cumulonimbi up there toward the Mogollon Rim.
11:07 AM. Unexpected sighting number two, ice! See center right frizzy, smooth area in “exhaust” part of Cu.11:37 AM. Unexpected sighting #3: Didn’t think those turrets could extrude so far into the extremely dry air above those tops, but there it is, extruding like anything. (Center right). Also note the ice in the lower tops, left center, and the hint of a rain shaft! Unbelievable. The dark blob at left in mid-air, obscuring a portion of the cloud, is a pipevine swallowtail butterfly that surprised me by flying into the frame as I snapped the photo. Yesterday may have been the most surprising day of my life, maybe yours, too. 2:18 PM. “USN4”: This gargantuan cell up there by Globe. Unbelievable that a cell this big was so close to our area considering all the dry air that was moving in.
2:28 PM. A surprisingly thin turret that has gone completely to ice (right side). The extruding turret on the left, certainly would have some ice in it, but also, as you can see from its texture, has a lot of liquid cloud droplets in it, too. This is a nice example of the glaciation cycle in a small cloud.
3:40 PM. Showers, and likely some thunder out there, just a few miles N of the Biosphere 2 facility. A pretty scene since the blue of the sky is darker now as the sun’s elevation sinks toward the winter solstice.
3:48 PM. Thunder beyond the Lemmon. The turret on the left has converted to all ice, while the mounding one in the center, still has some liquid cloud droplets. The “soft-serve” look on the left, compared to the crenelations of droplet clouds, in particular, that darker turret in the center, is due to the differences in concentrations between the two phases. There are always fewer ice particle concentrations than droplet concentrations in clouds, and so droplet clouds look thicker, have sharper edges, more detail. But, we’ve been over this more than a few times. Sorry to belabor the point.
The weather way ahead
Mods continuing to show rain in our area sometime between the 6th and 12th of September, which would result in a non-rainless September. Sometimes, those mods think its due to a tropical storm remnant of a tropical storm that hasn’t formed yet. So, its quite mystical, that rain.
Still, the indications are that some rain will return after the long dry spell ahead.
A measly 0.01 inches is all we got here yesterday in a Seattle-like rain from an overcast that sputtered drops drown over a couple of hours, one that could barely wet the pavement, if we had any here in Sutherland Heights. Of course, we surely drooled at the close call that drained Saddlebrooke yesterday afternoon (see below). Probably washed more golf balls into the CDO wash like that storm did last year…
Also, 0.75 inches fell, too, where Ina crosses the CDO wash yesterday, “so close, and yet so far away”, as the song says. Oh, well, another missed rain that I have to crybaby about1. Will get some final pictures of the 2014 summer greening today before it fades away in the many dry days ahead to help make me feel better now that its over.
Here’s your cloud story for yesterday. It was pretty neat one, full of hope, even if that hope was eventually dissipated unless you lived in Saddlebrooke… The U of AZ time lapse film for yesterday is great, btw.
6:31 AM. I am going to say these are Altocumulus castellanus clouds, though they are a little low and large for that genera.
6:33 AM. This was a pretty scene… Here an isolated Ac cas rises up. Distant small Cumulonimbus clouds, weak ones, can be seen on the horizon.
9:18 AM. Before long, those pretty Cumulus clouds were springing to life off the Catalina Mountains, the sky so blue behind them.
9:19 AM. A rare “High Temperature Contrail” (HTC) slices through some very thin Altocumulus perlucidus. This aircraft phenomenon has also been called, “APIPs” for Aircraft Produced Ice Particles.) Recall that Appleman (1953) said that an aircraft couldn’t produce a contrail at temperature above about -35 C. But, he was WRONG. They can do it in a water-saturated environment at much higher temperatures, even as high as -8 C (see Rangno and Hobbs 1983, J. Clim. and Appl. Meteor., available through the Amer. Meteor. Soc. for free, an open journal kind of thing.)11:48 AM. Before noon, all thoughts of past glory were gone as the Big Boys arose in a hurry. What a dump here! The cloud, since it is not showing an anvil nor obvious fibrous appearance, still pretty cauliflowery even though the discerning CMJ would not be fooled by its icy composition, it would be a Cumulonimbus calvus (“bald”).3:40 PM. Probably THE most hopeful scene of the day. A large complex of Cumulonimbus clouds was emerging from the Tucson mountains, heading in this direction. But more importantly, were the cloud bases forming over Oro Valley ahead of it, likely, it seemed to be pushed upward by the outflowing winds ahead of the distant cells. Also, that cloud bases were forming and extending westward from the distant cells offered another rain-filled scenario that could happen as they approached from the SW.
4:14 PM. When the southwest wind arrived, it did in fact cause the clouds overhead to swell up like aphids on a Seattle rose bush, but as bad luck would have it, they were piling up just to the north of us and over Saddlebrooke where they all all those amenities and don’t really need a lot of rain.
4:40 PM. After the first base dropped its load a little beyond Saddlebrooke, another cloud base darkened and expanded over Saddlebrooke, but this time, began to unload there. Here, like the seldom seen pileus cloud, these strands of the largest drops being to pour out of the collapsing updraft. You have about two minutes to see this happen because if you look away, the next time you look there will be nothing but the “black shaft.”
4:45 PM. A remarkable transformation. How can so much water, you wonder, be up there in a cloud?
6:05 PM. As the threat of any significant rain faded away, there was at least some “lighting” excitement, produced for just seconds as the sun shone on this….Stratus fractus cloud. Again, you must be watching at all times to catch these little highlights.
6:58 PM. Time to say goodbye to Cumulus and Cumulonimbus clouds like these, until maybe next summer.
The End. Probably will go on a hiatus now.
——————–
1Its good to remember that there is a little crybaby in all of us, isn’t there?
First, this sight yesterday afternoon was interesting to me and I thought you should see it.
2:09 PM. Multi-strands of rain (aka, “dancing strands”) pour out of large, firm cloud base in Oro Valley. You won’t see such tiny features like this very often. Usually represent very large drops, formerly hail or soft hail we call graupel up higher. There are in this type of cloud always very tiny strands of graupel and hai aloft like this, but not so separated and so dense as here. The ones aloft might only be 10 yards (“meters”, if you’re thinking outside of football) wide. The rest of the rain shaft on the far right is in the fading mode, decreasing as the Cumulonimbus cloud above has exhausted its liquid water fuel (the part above the rain; its just rain, its “rained out”, no real cloud until much higher up when you get into the ice part, snowflakes.)
Second, it would appear that I hit the “publish” button before I intended to, before I really got going and figured out what I was going to say. I was no where near that button!
Third, this will be an assembly job, if anyone is out there, this piece will be gradually coming together, the nuerous errors being corrected on the fly, if it ever really does come together….
Maybe I will deflect attention with a spaghetti plot, get people wondering about that. Yeah, that’s a good idea. They won’t know what to make of it while I think up something to write.
Valid September 9th, 5 PM AST. I think you should really consider this today; talk to your friends about it. You might want to go to NOAA and look at all of them, to see how this one gets to this point. I strongly recommend that you do that.
Next, here is some rain data from Pima County. Then, some from the USGS. Dan Saddle, up there on Oracle Ridge looks to have gotten the most in a nearby gauge in the Catalinas, with 0.83 inches measured. Was that really the most that fell up in our mountains yesterday. Of course not! Not enough gauges to hit all the cores that struck those mountains, and its without doubt than 1-2 inches fell in the best ones.
2:10 PM.2:10 PM. Looking at a second core.2:17 PM. Combining cores.2:21 PM. Dancing strands storm joins the fray from the west, dark base about to unload.
In conclusion, Q. E. D.
In spite of the numerous heavy shafts of rain around yesterday, none formed above Catalina, except at the north end of town over there by Edwin Road where they had quite a dump in the middle of the afternoon. Only 0.12 inches here in the Heights of Sutherland. Still it was nice to see those Cumulonimbus blossom into such majestic clouds yesterday. So, today may be it for them, at least close to us. Here are a few more sights from yesterday’s fine day:
6:06 AM. Day started with some fine-looking Altocumulus castellanus, which, according to my cloud chart, one that can be found in fine school catalogs everywhere, it might rain within 6-96 hours. Worked out pretty well yesterday.9:34 AM. Of course, the best indicator of a good Cumulonimbus day ahead is tall spindly clouds like these. Shows the atmosphere is loaded with instability, or, if you really want to get fancy, CAPE (Convective Availiable Potential Energy). Clouds are going to mushroom up very easily, and way past the ice-forming level where rain will form.10:32 AM. And within the hour, rain was falling beyond the C-Gap.11:34 AM. A siting of the seldom seen “pileus” cap cloud on top of a rapidly rising turret. They were all over the place yesterday, but are “seldom seen” since they last only a few seconds as the turrets punch through them.12:18 PM. This pretty sight of Cumulus congestus with a remnant of a thin tower that had shot up and glaciated.12:34 PM. Within a few minutes, those two congestus clouds had erupted into this beauty with another pileus cap toward the north end of town.
6:43 PM. Trailing raindrops. The lack of visible ice at cloud top indicates low updrafts, and marginal ice formation, tops just barely reaching the temperature level where ice forms. That level tends to change some each day due to different aerosol and droplet concentrations, but is generally near the -10 C to -12 C level in Arizona. In oceanic regions, where clouds have larger drops and form drizzle and rain before reaching the freezing level, ice first forms in clouds closer to the -5 C level.2:09 PM. No ice or virga present.
“So what gives Mr. Weatherblogperson? Most clouds had no ice and a very, very few did, ones that had some rain fall out of them. Below I have handcrafted a diagram with too many arrows and text on it, just for you, my friend, to help explain the mystery of yesterday’s clouds. I think, or rather hope, the excess text and arrowing will be self-explanatory…..
The balloon sounding data from Tucson yesterday afternoon at 5 PM AST (launched around 3:30 PM, actually).
Overhsooting tops? Here’s the biggest one of the day yesterday. Most however, because they are colder than the environment, collapse quickly and as is often the case in days like yesterday, there is NO overshooting top by the time the ice and rain start to fall out the bottom of the cloud. But, you can bet before that happened there was one.
3:21 PM. Looking SSW toward Tucson at light rainshower with an overshooting top above most tops. Need a fatter arrow. That top is above and beyond the slope down part of Pusch Ridge.7:01 PM. The large patch in the distance would be Stratocumulus formed by the spreading out of Cumulus cloiuds.
First, before de-briefing yesterday’s disappointment, this happy map for early September.
Valid at 5 PM AST, Friday, September 6th. The models are really trying to help us out with our drought, and once AGAIN, they have come up with a doozy of a prediction to do that. Crunched by the illustrious WRF-GFS model from the 5 PM AST global data, millions and billions of calculations involved, btw, rigorous math employed, too, and look what popped out!
Some background in support of the map above:
Presently, we have the two Niños going (the newly written up in Nature, “Cal Niño”, and the regular “New Niño” down there in ocean region 3.4). This fall, that combination of two Niños gives us a huge leg up on having a significant rain from a tropical storm because both Niños, with their massive areas of above normal sea surface water temperatures, will help dying hurricanes get closer to old Arizony before falling apart. The warmer the water, the longer they last.
The forecast map above is no less than the THIRD model-of-some-kind’s prediction in the just past two weeks that a tropical remnant/center will go into Arizona. The first two weren’t even close, Julio, was it, that the Canadians said would go over Yuma a couple of weeks ago. And then the big one that is forming now was supposed to do come into AZy in one WRF-GFS model run about a week ago. Now the Big One, will die way out in the Pacific without even getting close.
What’s more, as the one person who reads this blog, you will know that we examine spaghetti to see if there is ANY credibility to such a long range forecast, most of which should be put in trash immediately. Here’s what made the above happy map even that bit happier, below, from the NOAA spaghetti factory. Its been annotated for your enjoyment
Valid on Thursday, September 5th at 5 PM AST. This map suggests, with moderate confidence, that a trough will exist along the West Coast, something that if in that location, will steer storms into Mexico or the SW US as they drift up the coast of Baja. The blue circles along the Baja coast clusters the position of the hurricane/tropical storm whose remnant may be steered thisaway. That yellow contour (5760 m) is the actual prediction that was made by the model of the “contour of interest”), and it shows that there was a little too much amplitude in it compared with what might actually happen (blue lines are generally not to far to the south. Please ignore the slight time offset (1 day) in the two maps. Its seems to be all that’s available…
So lots to be happy about this morning after a disappointing trace of rain yesterday here in The Heights of Sutherland.
Yesterday’s clouds
Boring, for the most part, though that clear slot to the west near sunset provided some nice lighting around. To wit:
8:16 AM. Overcast in Altostratus opacus, with some areas of Altocumulus.3:00 PM. Some excitement down the road over there by SaddleBrooke Ranch. One or two cells developed yesterday afternoon, in spite of the low temperatures (that’s 80s here in Arizona).3:14 PM. Other than a couple of shafts, the day looked pretty much the same on the way out as it did on the way in. Overcast Altostratus opacus with shreds of Cumulus fractus here.6:28 PM. Get cameras ready when you see a slot like this! The clouds are Altocumulus opacus, some virga off in the distance suggesting higher tops. Also, to the east, the clouds were Altostratus, a mostly ice cloud while here the cloud is mostly supercooled liquid water. How’s come? Frequently top tops of Altostratus, often at Cirrus levels, drop precipitously when troughs approach, and when that happens, you end up with a layer that is mostly ice-free. A sharp drop in cloud tops is what happened here. Those Altocumulus clouds, though dark looking are probably not even 3000 feet (1 km thick). Altostratus clouds are rarely less than 2 km thick.6:36 PM. Clear slot to the west caused this nice highlight to creep up the Catalinas.6:39 PM. The green of the 2014 summer.6:45 PM. Was still filled with hope that those distant Cumulonimbus tops would creep in overnight, at least produce some light rain as a stratiform deck. Didn’t happen.
Yesterday’s non-storm:
Dropped a lot of rain down in SE Cal and western Arizona; I guess we should be happy for them. Imperial, CA, at -49 feet elevation, got 1.46 inches! And areas around Yuma, nearly an inch.
But that trough flubbed up moving NE during the night. Below, the scene from 5 PM AST last evening when “little troughy” looked potent. From tSan Francisco State U/Haight-Asbury District/, this nice map:
Yesterday at 5 PM. Little troughy (LT) full of thunderheads and rain over there by Yuma. Passed over us last night, but the storms aged and fell apart as we do.
Going back to the possibility of a hurricane remnant hitting Arizona, something I seem to be stuck on, “If the left one don’t get you, then the right one will1” We’re talkin’ hurricanes here, not about fists and number nine coal. The many hurricanes and tropical storms that are forming this year, about one every five minutes it seems, including Lowell of late, and the monster that is forming now, will be moving too far to the “left” of Arizona, out into nowhere in the eastern Pacific to die with their life sustaining rains. But ….our day will come this year I think! remember our logo: “Right or wrong, you heard it here first!”
In the mid-60s this morning. Can it feel any more that fall is upon us this morning?
An unusually strong “trough” (a bend in the winds that points to the Equator) aloft will be moving across our region today, and as it does, it will be clustering storms, much like they were bunched together two days ago. Remember that those bunched thunderheads came through in a band about mid-day. Something similar is foretold for today, except a little later. We hope that it takes a little longer than about 25 minutes to go through today, too. Violent weather is expected in AZ today, too, with the PHX NWS office particularly worked up by this possibility and that office has already issued public advisories about frequent lightning, terrific winds, and huge dumps of rain.
Dry and fall like days will follow today…..meaning morning low temperatures will probably drop into the 60s here as the dry invading air moves over us. With the lower sun angle these days leading to deeper blue skies overhead, the lower morning temperatures, you will definitely be thinking about college fubball in the days ahead.
Pay especial attention to what Bob has to say, our premier senior heavy weather forecaster, and your NWS for watches and warnings. Mike at the U of AZ will be weighing in as well later this morning. Could it be a tube day, too, somewhere? Will be watching.
Not very certain there will be any more August rain here after this, a very dark thought. As you know the chances of rain start to decline at this time of year.
Looks like it needs to be updated…..
Yesterday’s clouds (not in chronological order, just because…)
Maybe I make it too easy for you every day…
Ice developed early and often in those morning Cumulus as they transitioned to weak Cumulonimbus clouds with tops that weren’t so high, but considering how early that happened, it led someone to think that it might be a really good thunderstorm day. But then the air aloft dried out and those Cumulus tops couldn’t reach the ice-forming level by afternoon, which was quite a disappointment for someone.
Here are some pretty cloud scenes for you:
11:01 AM. Ice is obvious here. But, what kind of ice? If you look closely you can see that the ice crystals in this glaciated turret are comprised of hollow sheaths and needles, since the top of this cloud modest; not that high and cold. Well, that’s what I thought, anyway, just something about the texture…. Those kinds of crystals form at temperatures higher than -10 C (14 F), which is an unusual occurrence in Arizona. Happened yesterday because cloud bases were warm to start the day (about 10 C, or 50 F). Huh? Seems like a non-sequitur. “Strangely believe it”, as we like to say here, ice forms at higher temperatures as the bases of the clouds get warmer because ice formation is tied to drop sizes. The warmer the bases, the larger the drops reaching the freezing level in Cumulus turrets, and those larger drops freeze at higher the temperatures.6:27 PM. A parheila or sun dog, or mock sun in Altostratus cumulonimbogentius (of course). Caused by ice crystals falling flat on their face, hexagonal plates, pristine ones, without any riming (cloud drops that have bumped into them and froze)7:02 PM. Evening Cumulonimbus with a nice rain shaft; sent a few bolts “down” which is technically incorrect since the most luminous thing you see is called the “return stroke” and actually is going from the earth to the cloud.)11:01 AM. Small Cumulonimbus forms over the Catalina Mountains. The turret on the left side is still mostly water, but would have a lot of small ice crystals in it. The center of the photo turret has glaciated, few or no liquid droplets exist.6:26 PM. Cumulus highlighted by the setting sun under Altostratus or Cirrostratus (take your choice–Cs can have shading late in the day, otherwise, no shading for Cs. So pretty a scene.Just a nice closeup of a Cumulus turret. The variation in shading displays the complicated arrangement of liquid water content in the cloud, those darker areas having more.9:43 AM. Going up? The Cumulus began forming on the Catalinas about 9 AM, a pretty early start, and that, a good sign of Cumulonimbi in our future.5:24 PM. Just another just a pretty scene with Cumulus humilis and congestus.
