Frosty, the Lemmon

When one first encounters this title with its unexpected play on words, we wonder what the author had in mind.   Of course, most of us know that at Christmastime, we are often regaled by a Christmas tune called, “Frosty the Snowman1“.   But here, we are surprised as we continue reading the title that instead of encountering the word, “snowman,” we encounter the word “Lemmon!”  Hah!

What is meant here?  What is author trying to tell us? Perhaps the word, “lemon”,  has been misspelled.   But if so,  why would a “lemon” be frosty?  Perhaps there was a cold spell in Florida and the author is harkening the reader to a long ago memory.  Or, perhaps misspelling “lemon” was a literary device to emphasize that word in an eccentric way.

Yet, upon further investigation, we find that the issue is more complexed than first imagined.  We find that there was an art teacher, nurse, and eventually, a self-educated botanist from New England, Sara Plummer Lemmon, who, with her husband and another worker, hiked to the top of the Catalina Mountains right here next to us, and while doing so, they logged the vegetation that was unique to the area.  In their excitement when reaching the top, they named that highest peak after Mrs. Lemmon.

So, what does this piece of history add to our literary dilemma encapsulated in the title?

Perhaps Mrs. Lemmon did some work in the field of glaciology as well, hence, the word “frosty” as a possible hint of that work.  Yet, upon investigation,  we find no mention of work on ice crystals, hoar frost, nor glaciology not only in the work of Mrs. Lemmon, but neither in the work of any the team that mounted what is now known as Mt. Ms. Lemmon.   We add that the note that the Lemmons, J. G. and Sara,  were on their honeymoon at this time, historians tell us.  Perhaps there is another avenue we can explore due to that latter element.

Could it be, too, that we are missing a characterization of Ms. Lemmon by our author?  Perhaps she was shy,  seen inadvertentlhy as “cold” by some, or was not particularly interested in the physical advances of her husband, J. G.  The word “frosty” alert may be alerting us those possibilities.

Ultimately, we remain perplexed by this title; it forms an enigma that may never be confidently resolved.

But then good titles,  and good books, are supposed to make us think,  try to imagine what the author is telling us through his/her use of metaphor and other literary devices, and  this title has done that.

We, of course, reject the most plausible, superficial explanation, that the author’s play on words was merely describing a local, snow and rimed-tree mountain named after Ms. Mt. Lemmon,  as in the photo below.  No, Occam’s Razor, the idea that the simplest explanation is usually the best one, will not do.

4:43 PM.
4:43 PM.  Those trees are rimed, like the airframe of an aircraft that collects drops that freeze and cause icing.  Here the wind blowing across the mountain top, and cloud droplets that were below freezing, hit the trees and froze over a period of many hours, creating this scene.  Its not snow resting on the branches.  That would’ve blowed off in the strong winds up there.

———End of Literary Criticism Parody Module———-

There was a rousing 0.24 inches of rain yesterday!  Our storm total has topped out at 0.89 inches!

In other photos from yesterday:

9:42 AM. Altostratus translucidus again, this time with bulging Stratocumulus giving portent of a good Cumulus day if the As clouds will only depart. They did.
9:42 AM. Altostratus translucidus again, with a few scattered Altocumulus cloud flakes, but this time with bulging Stratocumulus topping Samaniego Ridge, giving portent of a good Cumulus day if the As clouds will only depart and allow a LITTLE warmth.  They did.

 

10:24 AM. Before long, cloud bases darkened here and there, indicating mounding tops above a general layer, and with the low freezing level of about 7,000 feet, the formation of ice and precip was not far behind.
10:24 AM. Before long, cloud bases darkened here and there, indicating mounding tops above a general layer, and with the low freezing level of about 7,000 feet, the formation of ice and precip was not far behind.
10:51 AM. Mountain obscuring showers were soon in progress due to both a little warming, but also because of a cloud energizing swirl in the upper atmosphere that passed over us at 1 PM AST. Did you notice that windshift aloft as that bend in the winds went by up there? You probably noticed that it was no dice, er, no ice, after 1 PM as the mash down of air that follows "troughs" did that very effectively after 1 PM.
10:51 AM. Mountain obscuring showers were soon in progress due to both a little warming, but also because of a cloud energizing swirl in the upper atmosphere that passed over us at 1 PM AST. Did you notice that windshift aloft as that bend in the winds went by up there? You probably noticed that it was no dice, er, no ice, after 1 PM as the mash down of air that follows “troughs” did that very effectively after 1 PM.

 

10:52 AM. As the clouds (weak Cumulonimbus ones) broke, there was a fantastic rainbow for just a seconds to the north, landing on my neighbor's house.
10:52 AM. As the clouds (weak Cumulonimbus ones) broke, there was a fantastic rainbow for just a seconds to the north, landing on my neighbor’s house.  It was even better before this, but was slow getting to the camera!  Dang.

 

10:54 AM. Pictures a poppin' now as breaks in clouds allows highlights of glinting rocks and scruffy Stratus fractus or Cumulus fractus clouds lining Sam Ridge.
10:54 AM. “Pictures a poppin’ ” now as breaks in clouds allows those fabulous highlights of glinting rocks and scruffy Stratus fractus or Cumulus fractus clouds lining Sam Ridge, those highlight scenes that we love so much when the storm breaks.  And these scenes change by the second, too!

 

11:00 AM.
11:00 AM.
Also 11 AM. Out of control with camera now.....
Also 11 AM. Out of control with camera now…..

 

11:12 AM. Meanwhile, back upwind... This line of modest Cumulonimbus clouds fronted by a weak shelf cloud roared in across Oro Valley to Catalina. What a great sight this was since now there was a chance of some more decent rains!
11:12 AM. Meanwhile, back upwind… This line of modest Cumulonimbus clouds fronted by a weak shelf cloud roared in across Oro Valley to Catalina. What a great sight this was since now there was a chance of some more decent rains!  Before long, the rains pounded down, puddles formed, and another 0.18 inches had been added to our already substantial total of 0.65 inches.

 

12:01 PM. But that wasn't the end, was it? Before long, a heavy line of Cumulus and weak Cumulonimbus clouds formed again to the southwest and drenched Catalina with another round of rain, this time, only 0.06 inches. And with it came the End. This line of showers was spurred by that upper level wind shift that was going to occur over the next hour.
12:01 PM. But that wasn’t the end, was it? Before long, a heavy line of Cumulus and weak Cumulonimbus clouds formed again to the southwest and drenched Catalina with another round of rain, this time, only 0.06 inches. And with it came the End. This line of showers was spurred by that upper level wind shift that was going to occur over the next hour.

 

1:01 PM. Sometimes those clearing skies, the deep blue accentuating the smaller Cumulus clouds provide our most postcard scenes of the great life we have here in the desert.
1:01 PM. Sometimes those clearing skies, the deep blue accentuating the smaller Cumulus clouds provide our most postcard scenes of the great life we have here in the desert.
2:13 PM. While it was sad looking for ice in the afternoon clouds and finding none, the scenes themselves buoyed one.
2:13 PM. While it was sad looking for ice in the afternoon clouds and finding none, the scenes themselves buoyed one.  The instability was great enough that even brief pileus cap clouds were seen on top of our Cu.
2:21 PM. Pileus cap cloud (right turret) tops honest-to-goodness December Cumulus congestus cloud. No ice nowhere.
2:21 PM. Pileus cap cloud (right turret) tops honest-to-goodness December Cumulus congestus cloud. No ice nowhere.

 

2:28 PM. And if the sky and mountains splendor isn't enough for you, then consider our blazing fall-winter vegetation as evidenced by a cottonwood tree in the Sutherland Wash, that yellow dot, lower center.
2:28 PM. And if the sky and mountains splendor isn’t enough for you, then consider our blazing fall-winter vegetation as evidenced by a cottonwood tree in the Sutherland Wash,’ that yellow dot, lower center.  We have it ALL now!
2:48 PM. And, as the cloud tops are kept low, we get those fantastic, quilted, rich color scenes on our Catalina Mountains. Here, looking toward Charouleau Gap.
2:48 PM. And, as the cloud tops are kept low, we get those fantastic, quilted, richly colored scenes on our Catalina Mountains we love so much.  Here, looking toward Charouleau Gap and Samaniego Peak.   I could show you so many more like this from just yesterday!

 

5:08 PM. Even our lowly regarded teddy bear chollas have luster on days like this, the weak winter sunlight being reflected off its razor-hook-like spines.
5:08 PM. Even our lowly regarded teddy bear chollas have luster on days like this, the weak winter sunlight being reflected off its razor-hook-like spines, ones that many of us know too well.

 

5:12 PM. And like so many of our days here in old Arizony, closed out with a great sunset.
5:12 PM. And like so many of our days here in old Arizony, closed out with a great sunset.
 Possibility raised in mods for giant southern Cal floods, maybe some flooding in AZ floods, too

Something in the spaghetti plots has been tantalizing as far as West Coast weather goes.  They have been consistently showing a stream of flow from the tropics and sub-tropics, blasting into the West Coast.  Recall that yesterday, that tropical flow was so strong and so far south, that at least one major gully washed was shown to pass across central and southern California on New Year’s Day, but weaken and shift to the north of southern AZ after that.

Well, my jaw dropped when this model run from yesterday at 11 AM AST came out, re-enforcing, even raising the bar on flooding, in central and southern California, and with those stronger storms, the possibility of flooding and major winter rains here in Arizona was raised.  The severity of the pattern shown aloft is not one I have seen before, and for that reason alone,  might be considered somewhat of an outlier prediction, one really not likely to occur.

Now, while there is some support in this model flooding “solution” in the spaghetti plots, the main reason I am going to present a series of what a disastrous Cal flood looks like is just FYI and how it develops.  The closest analog to this situation was in January 1969 when a blocking high in the Gulf of Alaska (GOA), forced the major jet stream far south across the central and eastern Pacific on several occasions producing disastrous floods in southern California in particular, where one mountain station received more than 25 inches of rain in ONE DAY!

Also that blocking high in the GOA in Jan 1969 also forced unusually cold air into the Pac NW, where Seattle (SEA-TAC AP) accumulated 21 inches of snow over the month, still a record.

Here we go, in   prog maps of our WRF-GFS rendered by IPS MeteoStar:

In the Beginning, the blocking high, shunting the jet stream to the south and to the north takes shape in the GOA. Note low far to the south between Hawaii and southern California. Get sand bags out now!
In the Beginning, the blocking high, shunting the jet stream to the south and to the north takes shape in the GOA. Note low far to the south between Hawaii and southern California. Get sand bags out now!  This is for 11 PM AST, 28th of December.

24 h later:

Valid at 11 PM AST 29 December. Southern Cal flooding underway.
Valid at 11 PM AST 29 December. Southern Cal flooding underway.  Cold air pocket in Oregon has slipped southwestward helping to energize the lower band of jet stream winds by bringing cold air out over the ocean.  The greater the temperature contrast between the north and the south, the greater the speed of the jet stream between the deep warm air to the south, and the deep cold air to the north.  Note, too, high is getting farther out of the way in the Gulf of Alaska.

The situation continues to strengthen, and leads to this Coup de Gras, 11 PM AST January 1st.  A system this strong barging into southern Cal is mind-boggling, and this panel is what brought this part of the blog, to show you what a devastating flood in that area would look like:

Valid at 11 PM, January 1st. In my opinion, I doubt the Rose Bowl game between the Oregon Ducks and Florida State would take place.
Valid at 11 PM, January 1st. In my opinion, I doubt the Rose Bowl game between the Oregon Ducks and Florida State would take place in Pasadena, CA, if this were to transpire.

Now for AZ.  Here’s the prog for 12 h later, 11 AM AST January 2nd, Cactus Bowl Day in Tempe, AZ between the Washington Huskies and the Oklahoma A&M Aggies, to continue with sport’s notes here.  Rain would be expected for that game should this pattern persist:

Valid at 11 AM AST, January 2nd. This is an unbelievably strong wave that has roared in from the lower latitudes of the Pacific. While it rushes through Arizona in a hurry, heavy rains, and some flooding are likely should things transpire like this.
Valid at 11 AM AST, January 2nd. This is an unbelievably strong wave that has roared in from the lower latitudes of the Pacific. While it rushes through Arizona in a hurry, heavy rains, and some flooding are likely should things transpire like this.

Now for a gee-whiz, scary analog….one from WAY back in the winter of 1861-62 when the situation decribed above was likely very similar to what it was in that terrible flood; severe cold in progress in the Pac NW, as it would be in the upcoming situation; a tropical torrent raging in from the Pacific.   This 1861-62 flood episode is still remembered.  However, it went on for 30-40 days (!) with recurring episodes turning much of California’s central valley into a lake, Los Angeles area, too, where there was a report of 35 inches of rain in 30 days.

What’s ahead, really?

Well the models are going to fluctuate on the strength of this breakthrough flow “underneath” the blocking high in the Gulf of Alaska.   But almost certainly one major rain event will break through as that this happens.   Its kind of a fragile flow regime, so it usually doesn’t last long.

Whether it will be stupefyingly historic,  or just another ordinary southern Cal gully washer, can’t be pinned down.  But, if you lived down there, you’d want to be looking around and seeing what you could do to divert water, fix a roof, etc.

There would be strong, damaging winds with one of these “coming-in-underneath”, too, and, for surfers,   giant waves!

Interesting times ahead!  “Floodmagedon”, as we like to say these days?

No real weather here for awhile, except around Christmas when a mild cold snap, and a little chance of precip occurs as a cold front goes by.

The End, for awhile.

—————————–

1The most intellectually satisfying version of “Frosty the Snowman” was, of course, has been rendered by Bob Dylan.

Morning rain

The first of a couple of patches of rain over the next 36 h are passing through now,  R at this second, 4:40:32 AM, and 0.09 inches of rain so far.  Nice.

U of AZ Wildcat mod run at 11 PM AST last night has intermittent light rain most of the day here now.  What a great model run!

And with the last troughy coming across tomorrow during the day, with another chance of light rain then, too.  Looks like we’ll easily go over 2 inches for the month of December (1.94 inches now), the first above normal in rainfall winter month since November a year ago.

 Yesterday’s clouds and flowers

Not as widespread or dense as expected in the afternoon, but prettier, which helps counteract error.  Let us begin our review of clouds with some paper flowers; there are still some blooms out there!  Amazing.

8:25 AM. Seen on a dog walk under overcast Altostratus.
8:25 AM. Seen on a dog walk under overcast Altostratus.  Desert marigolds still going strong.
8:38 AM. Classic Altostratus, some virga apparent below thickest part
8:38 AM. Classic Altostratus, some virga apparent below darkest part.  Saguaro cactus is extruding slowly from the ground on the right.  Need time lapse to really see it do anything.
11:17 AM. Deeper clouds have moved away and now comes lower, shallow Altocumulus clouds some spewing virga.
11:17 AM. Deeper clouds have moved away and now comes lower, shallow Altocumulus clouds some spewing virga.  Photo annotated for Mark Albright, University of Washington research meteorologist who lives in Continental Ranch, and thus in the Tucson morning smog tide.

 

3:27 PM. One of the prettiest scenes of the afternoon, this array of Altocumulus.
3:27 PM. One of the prettiest scenes of the afternoon, this array of Altocumulus.

 

3:27 PM also. Only the extra special Mark IV cloud maven personage would have caught this aircraft ice trail, originally within those lower Altocumulus clouds, much too warm for normal contrails.
3:27 PM also. Only the extra special Mark IV cloud maven personage would have caught this aircraft ice trail, originally within those lower Altocumulus clouds, much too warm for normal contrails.  This is probably around 30 min old.

 

5:12 PM. Sunset in leading bank of clouds that led to the light rain this morning.
5:12 PM. Sunset in leading bank of clouds that led to the light rain this morning.

 

The weather way ahead

Threat of a larvae killing cold wave later this month fading; looks like that cold air will end up in the eastern US now, and no further precip after the series this week.  Darn.

The End.

Another fireball over Tucson! Backwards halo seen, too! Rain on tap

Check these out in yesterday’s “Olympics of optics” where all kinds of goofy optical things were seen:

3:19 PM. Fireball crosses Tucson skies.
3:19 PM. Fireball crosses Tucson skies leaving long plume of “smoke.”  Photo not touched up in any way shape or form because that would be wrong.  Note: always carry your camera with you since you only have seconds to capture something like this.
3:19 PM Fireball crosses Tucson skies 2.
3:19 PM Fireball crosses Tucson skies 2.

 

DSC_0438
3:57 PM. Then there was this “wrong way1” partial halo a few minutes later.  Could it be another  sign of climate change, as almost everything that happens is? The sun is below the bottom of the photo; haloes are supposed to go around the sun not around nothing.  When a partial halo around nothing occurs like this, its called a “circumzenithal arc”  caused by tiny, pristine ice crystals like hexagonal plates.   If you want to read about optics of all kinds, go  to the University of Washington Huskies weather department where they have optics chapter online.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4:10 PM. Contrail passes through or above Cirrus uncinus. Yesterday was one of the top (worst) days for contrails above and in view of Catalina IMO.
4:10 PM. Contrail passes through or above Cirrus uncinus. Yesterday was one of the top (worst) days for contrails above and in view of Catalina IMO.  Note lines of contrails above and behind weather station. We hope it was due to an unusual confluence of conditions such aircraft flying a heights different from normal due to a peculiar wind profile, Cirrus moisture at the level of the airways, that kind of thing since we rarely see as many as yesterday.

 

 Today’s clouds

Thickening and lowering, ho hum, the usual as a trough aloft (bend in the jet stream winds up there) off southern Cal and Baja approaches today.  Ahead of the bend in the winds, seen in the map below, the vast layers of air rise ever so gradually, something like cm per second.   But, its enough to produce sheets of clouds.

What kind of clouds?

Heavy, dense and gray ice clouds we call Altostratus (As), with thicker and thinner spots should dominate the day.  Then as the moist layer lowers,  that is, as the As  “bases”,  really just comprised of falling snow that only looks like a solid bottom, get lower, patches of virga will start to reach the ground later today.  Altocumulus ought to be around, too, water droplet clouds not cold enough to be completely iced up.  Expecting those layer clouds, or undercutting layers to be low and lumpy enough to be termed Stratocumulus late in the day.

Rain?

The strongest winds at 500 mb (around 18,000 feet above sea level) will be to our south beginning today, a necessary condition for virtually ALL wintertime rain here.  CM is expecting some rain to fall in Catalina later today, or tonight as this bend in the winds aloft goes by.  Expected amounts in this first wave,  trace, minimum to 0.25 inches max by mid-day tomorrow.

Its really dicey situation since its not clear how deep the moisture is off Baja now, but looks potent enough for as much as a quarter inch from this keyboard, though less is more likely.  Sorry the range is necessarily so great.

BTW, the WRF-GOOFUS model didn’t have ANY rain predicted for this time frame period in both of the 5 AM  AST and 5 PM  runs of yesterday.   So, we’re out on a bit of a limb.

After tommorow….

After 5 PM AST tomorrow,  all peoples and models see more rain for Catalina as two waves/troughs barrel in right behind the first one that goes over tonight.  The 2nd and 3rd ones produce a couple of rains through Thursday with big breaks likely in between.

The total amounts for Catalina between now and Friday morning still look like they will be contained within the range of  0.25 inches (things don’t go so well;  disappointing really) and an inch (things go really well).  Best guess is average of those, for a few day total of 0.625 inches.

The End

———————————

1Remember “Wrong Way Corrigan”? Picked up that fumble and scored a TD for the other team?  Maybe it was an early sign of the effects of concussions in fubball.

 

 

 

Spaghetti is back!

Due to some kind of server meltdown, the NOAA spaghetti plots, better,  “Lorenz plots” in honor of “Dr. Chaos”,  Edward N. Lorenz,  the ones my fans1 like so much,  have not been available.

But they’re back today!

But what are they telling us?  Gander this for Christmas Day:

Valid at 5 PM AST Christmas Day, December 25 th. I've annotated it especially for you.
Valid at 5 PM AST Christmas Day, December 25th.  I’ve annotated it especially for you.  The view is one where your looking down at where Santa lives from a big tower.  Not all annotations are accurate.

Don’t need to tell you that the weather looks like there’s a good chance of cold and threatening weather for Christmas Day.  Big trough implanting itself in the West around then.  Maybe those easterners who hogged all the cold air last winter will share some of it this winter.   The warmth we had last winter made it bad for horsey with all the fly larvae that survived.

Kind of bored now with the rain immeidately ahead, but only because everybody else is talking about it, too.  Its no fun when you don’t have a scoop and you’re just saying things that other people are already saying.  Even my brother in North Carolina, who knows nothing about weather,  told ME that it was going to rain here on Thursday!  How lame is that?  Of course, it is true that you won’t here anywhere else that the chance of measurable rain is more than 100% this week in Catalina ; at least I still have that.  Tell your friends.

When does it fall?  Sometime, maybe multiple times,  between Tuesday afternoon and Friday morning.   Hahaha, sort of.

Looks like the first trough and weather system will go over on Tuesday through Wednesday, chances of rain then, and yet another colder one on Wednesday night into Thursday.  So, 100% chance of measurable rain falling sometime between Tuesday afternoon and Friday morning, probably in several periods of rain.   Look for a frosty Lemmon Friday morning.

Predicted amounts from this keyboard?  Think the bottom of this several day period of individual rain events will be only a quarter of an inch.  Top, could be an inch, if everything falls into place.  Canadian mod from 5 PM AST global data yesterday, for now has dried up one of the storms, that on Thursday, the day the USA! model thinks is our best chance for good rains based on the virtually same global data!  Of note, the USA model based on 11 PM AST data, has begun to lessen our Thursday storm that bit.

This is the reason that the certainty of measurable rain here in Catalina is spread over such a several day period.

Your cloud day yesterday

Just various forms of Cirrus,  most seemingly from old contrails that produced exceptional parhelias (sun dogs, mock suns).

Very contrail-ee sunset, too,  as contrail lines advanced from the west.  They were likely more than an hour old when they passed over Catalina yesterday.

10:56 AM. Glistening rocks after the rain. Very nice.
10:56 AM. Glistening rocks after the rain. Very nice. Cu fractus at moutain tops.

 

2:36 PM. Nice example of the rare seen Cirrostratus fibratus (has lines in it).
2:36 PM. Nice example of the rare seen Cirrostratus fibratus (has lines in it).  Hope you logged it.

 

3:42 PM. Looks like old contrails to this old eye, resembling CIrrus radiatus. The "radiating" aspect may be due to perspective.
3:42 PM. Looks like old contrails to this old eye, resembling CIrrus radiatus. The “radiating” aspect may be due to perspective.

 

3:50 PM. Parhelia lights up in CIrrus. These, due to the high speed of Cirrus movement, only last seconds in thin streamers like these.
3:50 PM. Parhelia lights up in CIrrus. These, due to the high speed of Cirrus movement, only last seconds in thin streamers like these.  To get really spectacular optics the crystals up there have to be especially simple, like plates and stubby columns, maybe prisms as well.  When aircraft create contrails, there is an excess of ice crystals, far more than occur in natural Cirrus as a rule, and due to that high concentration, can’t grow much and usually stay as simple crystals, not develop complicated forms like bullet rosettes, crystals with stems sticking out every which way.
5:23 PM. Contrail-ee sunset. Pretty, but awful at the same time, since it shows how the natural sky can be impacted by us in our modern lives.
5:23 PM. Contrail-ee sunset. Pretty, but awful at the same time, since it shows how the natural sky can be impacted by us in our modern lives.  You wonder how much of us the earth can take?

The End

 

 

—————–

1Why just recently C-M had a comment from a fan in Lebanon3,  that country near Israel, not the one in Ohio2!  Said it was warm there now, but normally it rains for days at time in the winter, and gets real cold.  You see, the eastern Mediterranean is, climatologically speaking, a trough bowl.  Troughs just hang out there a lot, creating something called the “Cypress Low.”  Though it only rains in the cool season, October through May,  as in Israel,  places in Lebanon get 25 -40 inches of rain during that time, and its exciting rain because it almost all falls from Cumulonimbus clouds, many with lightning! C-M is getting pretty excited, since he’s on record as wanting to go Lebanon to study the clouds there!  See Lingua Franca article from 1997!  He loves those Mediterranean wintertime Cu.  Hell, you probably threw it out, so here it is: Lingua Franca _1997.  See last sentence. last page.  Thanks.

2Speaking of Ohio, who can forget that great 1980s rant against urban sprawl in Ohio by Chrissie Hinds and the Pretenders!  Will it happen to Catalina after the road project?  An insurance agent told me that Catalina was to be absorbed by Oro Valley after it was completed.  Oro Valley says they know nothing about that.

3“Its great when you’re global!”

A rainy, drizzly Catalina day; 0.69 inches in The Heights

Yesterday’s cold front packed a few more rain “calories” than expected….  Kind of wrecked my play on beer in yesterday’s blog title as a way of making fun of it, you know, “Front light”.    See rain amounts below.

—————

But before that, a heads up:  1) More rain on way next week, at least a 100% chance of measurable rain during the week, and more storms after that (people will be complaining before long);

2) there are some pretty cloud photos at the very bottom in case you’d like to skip over a lotta verbiage;  quite dull writing, hand-waving, that kind of thing about what happened yesterday.

=============

Personal weather station totals as of 2 PM AST yesterday as rain ended.
Personal weather station totals as of 2 PM AST yesterday as rain ended from the Weather Underground map.  The green and yellow areas are radar echoes, yellow the stronger ones.

The official totals are pretty amazing, too, considering our best model was predicting something like 0.01 to 0.10 inches here in Catalina just before the rain started1.  Note below the 2.20 inches at Mt. Lemmon.  BTW, we’re now just about at our average rainfall total for December here in Catalina of 1.86 inches and we’ve gotten 1.85 inches so far.

Here’s a truncated rain table for our area from the Pima ALERT gauges (its a rolling archive and so you’d better get there early if you want to see the full lineup of totals for yesterday’s storm):

Pima County Regional Flood Control District ALERT System:  Precipitation Report
                              
              Precipitation Report for the following time periods ending at: 04:14:00  12/14/14
                       (data updated every 15 minutes)      
              Data is preliminary and unedited.
              —- indicates missing data
                          
    Gauge    15         1           3          6            24         Name                        Location
    ID#      minutes    hour        hours      hours        hours
    —-     —-       —-        —-       —-         —-       —————–            ———————
Catalina Area
    1010     0.00       0.00       0.00        0.00         0.51      Golder Ranch                 Horseshoe Bend Rd in Saddlebrooke
    1020     0.00       0.00       0.00        0.00         0.55      Oracle Ranger Stati          approximately 0.5 mi SW of Oracle
    1040     0.00       0.00       0.00        0.00         0.63      Dodge Tank                   Edwin Rd 1.3 mi E of Lago Del Oro Parkway
    1050     0.00       0.00       0.00        0.00         0.55      Cherry Spring                approximately 1.5 mi W of Charouleau Gap
    1060     0.00       0.00       0.00        0.00         0.75      Pig Spring                   approximately 1.1 mi NE of Charouleau Gap
    1070     0.00       0.00       0.00        0.00         0.67      Cargodera Canyon             NE corner of Catalina State Park
    1080     0.00       0.00       0.00        0.00         0.59      CDO @ Rancho Solano          Cañada Del Oro Wash NE of Saddlebrooke
    1100     0.00       0.00       0.00        0.00         0.43      CDO @ Golder Rd              Cañada Del Oro Wash at Golder Ranch Rd

Santa Catalina Mountains
    1030     0.00       0.00       0.00        0.00         0.47      Oracle Ridge                 Oracle Ridge, approximately 1.5 mi N of Rice Peak
    1090     0.00       0.00       0.00        0.00         2.20      Mt. Lemmon                   Mount Lemmon
    1110     0.00       0.00       0.00        0.00         0.55      CDO @ Coronado Camp          Cañada Del Oro Wash 0.3 mi S of Coronado Camp
    1130     0.00       0.00       0.00        0.00         0.79      Samaniego Peak               Samaniego Peak on Samaniego Ridge
    1140     0.00       0.00       0.00        0.00         0.71      Dan Saddle                   Dan Saddle on Oracle Ridge
    2150     0.00       0.00       0.00        0.00         1.34      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         0.98      Marshall Gulch               Sabino Creek 0.6 mi SSE of Marshall Gulch

Hell, there wasn’t any rain in the cloud band west of us when I got up, and so I thought with some lifting, and that jet core at 500 mb slipping southward from southern Cal as the day went on, rain would develop farther south in the frontal cloud band.  It did, of course, but still thought it would blow through in 2 h or so, something akin to the models as well.   The rain fell for about 5 and half hours!  The clearing took place a little before sunset, not in the early afternoon as expected.

So what happened?

I think you and I  overlooked a disturbance aloft behind the frontal band.  It was sliding SEwd fast from Nevada, catching up to our little frontal band. When those things happen, clouds magically seem to be appearing on the backside of the frontal band, fattening it up, holding its progress back; and the rain areas get bigger.  The frontal band was MUCH fatter when it went by TUS than it had been just a 100 or so miles to the west at 4 AM AST yesterday morning.  Here are contrasting satellite and radar images for two periods yesterday, before the band fattened up and the second, when it was raining so much here:

Satellite and radar imagery for 4:30 AM yesterday. Sneaky backside disturbance is represented by those clouds near Vegas.
Satellite and radar imagery for 4:30 AM yesterday. Sneaky backside disturbance is represented by those clouds near Vegas.  No rain echoes west of Catalina, stop along the Pima County line making it look like rain will be marginal here.
BY 1:30 PM in this satellite image with radar, the band is twice as wide and there's rain all the way down to Mexico way.
BY 1:30 PM in this satellite image with radar, the band is twice as wide and there’s rain almost all the way down to Mexico way.  Look how those clouds and showers near Vegas have caught up with our front, almost attaching themselves to it in north central Arizona.  Lots of times this process of upper air disturbances catching up to a front generates a cyclone along the front as the front widens and begins to kink.  I think that’s what happened anyway.  Whatever.  It was a great confluence of events for us here in Catalina.  Think how the wildflower seeds are feeling right now with already an average amount of rain for December, and its not half over, and more is on the way, yay!

If you’re a true C-M disciple you noticed something else yesterday:  true DRIZZLE in the rain.  Drizzle may be even more rare than snow here.  And the thick low visibility rain consisting of smallish drops from drizzle sizes, 200-500 microns (a couple to a few human hairs in diameter)  and raindrops just above those sizes for much of the time the rain fell,  should have made you start thinking of a warm rain process day.  Maybe there was no bright band in the radar imagery during those times, something that happens when rain is ONLY formed by colliding drops that get big enough to fall out; no ice nowhere.  In the heavier rains, sometimes when visibility was improved, ice was very likely involved.

The TUS sounding really can’t shed light on this question since the morning was had shallow clouds that weren’t raining yet, tops barely below freezing, and the 5 PM AST sounding, with tops at -10 C (14 F), was a little too late, though that layer that was sampled did produce what appeared to be ice virga in the direction of TUS about the time of the sounding.    BTW, its well known that “warm” rain processes that don’t involve ice occur at temperatures below freezing, so the expression is a bit of an oxymoron.

So, without radar imagery over us during the time of the thick rain and drizzle, we can’t say for sure, but it sure looked like it to C-M, which is  what you should think as well I think.  Thanks in advance for thinking what I think.

Enough of my excuses2, let’s rock and roll with yesterday’s clouds

Your cloud day

7:35 AM. Light rain, looking suspiciously like "warm" rain, spreads over the Catalinas. Its only gonna get better from here and frontal band barrels in on Catalina.
7:35 AM. Light rain, looking suspiciously like “warm” rain, clouds not looking so deep, spreads over the Catalinas. Its only gonna get better from here as frontal band leading edge is just across the street over there on the Tortolitas.

 

 

8:09 AM. "Oh, what a crummy front, things breaking up already", you were thinking. Also, "Look at how shallow those clouds are! Terrible." Sometimes these brief thin spots or clearings are called, "sucker holes."
8:09 AM. “Oh, what a crummy front, things breaking up already”, you were thinking. Also, “Look at how shallow those clouds are! Terrible.” Sometimes these brief thin spots or clearings are called, “sucker holes.”  Hope you didn’t fall for it like I did.  (Just kidding.)
9:43 AM. R--F (text for "very light rain and fog"), rain has piled up to 0.10 inches. But you notice there's something different about the rain, its thicker, smaller drops, even drizzle drops in it. You begin ask, "Could this be a solely warm rain event?" I think so.
9:43 AM.  W0X1/2 R–F (text for “indefinite ceiling,  zero, sky obscured, visibility 1/2 statute mile in very light rain and fog”), rain has piled up to 0.10 inches by this time. But you notice there’s something different about the rain; , its thicker, small thick drops hardly making a splash in puddles, even drizzle drops in it. You begin ask, “Could this be a solely warm rain event?” I think so. Note disappearing telephone poles.
12:46 PM. After several hours of rain, flood waters begin to appear. Note mottled surface of this lake, showing that the drops were making good splashes at this time. Rain intensity deemed R (moderate) then.
12:46 PM. After several hours of rain, flood waters begin to appear. Note mottled surface of this small rain-formed lake, showing that the drops were making good splashes at this time. Rain intensity deemed R (moderate) then.  Deemed not a warm process rain at this time due to those drop sizes and less bunching, fewer small drops in between the larger ones, visibility was about 2 miles in rain.

The best scenes of all were when the clouds began to part in the late afternoon and evening sun.  I hope you caught these beautiful scenes:

DSC_0405 DSC_0403 DSC_0387 DSC_0377

The End

—————————————————–
1Total rain prediction from our best model, the one from the U of AZ with the predicted totals through 3 PM AST yesterday. The model run was at 11 PM AST the evening just before the rain began:

Ann RaIN THROUGH 3 PM 12-13
The arrow points to our location, in which only a tiny amount of rain was predicted. Mod doesn’t miss very often by this much, but the earlier December storm had the same mod problem, too little in the model compared to what actually fell here. Gee, new thought… Could it be a poor representation of the warm rain process? Hmmmm.

 

2Your Catalina C-M did have a correct range of amounts that could fall in yesterday’s storm right up until the last minute.  For weeks he was predicting, and staying firm with, 0.15 inches on the bottom, and a voluptuous, if that’s the right word, 0.80 inches potential on the top.

 

 

“Front Light”; compare to Bud Light

Front will roar across like a mouse, not a lion, as hoped for a few days ago.  Not too many rain “calories” in it.  Measurable rain will still occur, starting sometime between 9 AM and 10 AM AST–oops. raining now at 7:10 AM!   Check out U of AZ model for rain timing.   First drops fall here in that model output (from 11 PM AST last night), between 8 AM and 9 AM.  The frontal band, such as it is, is almost here!  However, the model rain tends to arrive  a little fast here,  though not always.  FYI, be on guard.

C-M is holding firm with a minimum of 0.15 inches today, but previous foretold possible top of 0.80 inches a few days ago is out of the question.  Will be happy with 0.25 inches at my house.  Since I am also measuring the rain as well as forecasting it, I have a feeling things will turn out fine.

There will be a nice temperature drop, windshift, and simultaneous rise in pressure as the cold front goes by–it’ll be fun for you to watch the barometer today and see the minute the front goes by as higher pressure begins to squash down on you.

Rain might reach briefly moderate intensity (defined by official weatherfolk as 0.10 to 0.30 inches per hour).  It would be great if it lasted an hour at that rate, but it likely won’t.  Its moving pretty fast, and it doesn’t seem like more than 2 h of rain can occur today.  Look for a nice clearing in the afternoon, and a COOL evening.

Drive south if you want to avoid rain today.  Jet core (in the middle levels, 500 millibars, 18, 000 feet above sea level) is almost overhead, and just to south, and that core is almost a black-white discriminator of rain here in the cool season.  So, we’re on the edge of the precip today.  More to the north;  less to the south.

Some clouds for you

1O:55 AM, December 11. Thought you should see this nice line of Ac castellanus and floccus underneath Cirrus spissatus.
1O:55 AM, December 11. Thought you should see this nice line of Ac castellanus and floccus underneath Cirrus spissatus.
7:02 AM. Sunrise.
7:02 AM. Sunrise.
12:32 PM. Wind picking up at the ground and aloft. Note tiny Ac lenticular with Cu fractus clouds.
12:32 PM. Wind picking up at the ground and aloft. Note tiny Ac lenticular with Cu fractus clouds.
3:14 PM. The high cloud shield from the storm encroaches. Could call this either Cirrus spissatus or Altostratus translucidus.
3:14 PM. The high cloud shield from the storm encroaches. Could call this either Cirrus spissatus or Altostratus translucidus.
5:22 PM. Now we're talkin' Altostratus with underlit mammatus and fine virga.
5:22 PM. Now we’re talkin’ Altostratus with underlit mammatus and fine virga.  So pretty.
5:29 PM. A late "bloom", not really expected. Shows that there was a clear slot far beyond the horizon. Had to pull off by the Refuse Waste station on Oracle to get this. I hope you're happy.
5:29 PM. A late “bloom”, not really expected. Shows that there was a clear slot far beyond the horizon. Had to pull off by the Refuse Waste station on Oracle to get this. I hope you’re happy.

The weather ahead and WAY ahead

Speaking of bowls, and let’s face it, with only a 100 or so we could use a few more1; we here in all of Arizona are in the “Trough Bowl” now.

This means that troughs (storms and cold fronts)  that barge into the West Coast will gravitate to Arizona instead of bypassing us and they will do that over and over again.    Being in the Trough Bowl is great fun! Lots of weather excitement for weather-centric folk like yours truly.    When you’re in the Trough Bowl, the weather is “unsettled”;  is NEVER really nice (if you like sun and warmth) for very long because a new front/trough is barreling in at you.

So, while today might be a little disappointing,  we will have many chances to get the “real thing”, i.e., a behemoth of a trough among the many that affect us in the weeks ahead.

In the longer view, a behemoth of a trough for the Great SW has just popped out of the models1 just last night in the 11 PM AST run! Gander this monster truck trough for AZ.  Where’s that monster truck event announcer, we need him now!

Valid for 11 PM AST, Christmas Day! Wow. Can't really take this at face value that far out, but if it did happen, likely would be snow in the Catalina area, and horsey would likely need a blanket after it went by. Will keep you informed periodically about this as the days go by.
Valid for 11 PM AST, Christmas Day! Wow. Can’t really take this at face value that far out, but if it did happen, likely would be snow in the Catalina area, and horsey would likely need a blanket after it went by. Will keep you informed periodically about this as the days go by.

OK, enough weather “calories” for you today.   Hope you’re excited like me.

The End

———————————————

1Furthermore, why don’t we have bowls for women’s teams, what happened to Title IX there, maybe Beach or Sand Football? )

2As rendered by IPS MeteoStar, which is about to go from “free” to “fee” in January.  Dang.

Rain continues to fall in Catalina on the 13th

Today is the 9th.

Great news!  Another decent rain assured now sa the models have converged on rain here on the 12th during a nice, and very sharp cold front passage, those in which the temperature can fall from a toasty 60s to 43 F over an hour along with a withshift to the NW from gusty SW winds.   So we have quite a dramatic weather event coming up.  Here’s what the Canadians have to say about it:

Valid at 5 PM AST, December 13th. Areas where the model has calculated precipitation during the prior 12 h, are marked, from light to heavier amounts, green to blue to yellow. There's a little yellow in Arizona north of Catalina.
Valid at 5 PM AST, Saturday, December 13th. Areas where the model has calculated precipitation during the prior 12 h, are marked, from light to heavier amounts, green to blue to yellow. There’s a little yellow area of heavy precip over Catalina (see arrow, lower right), and that’s why I am posting this panel!

But what does it all mean, all the models predicting rain for Catalina on the 13th?   Here’s what it means:

The chance of measurable rain here on Saturday,  the 13th is now more than 100 %; its in the bag.  Count on it.  This is weather forecasting at its best.  The rain may start in the early morning hours of the 13th.

The models have varied drastically on the amounts of rain, and so there’s quite a range that could occur.  From this keyboard:

Minimum amount is 0.15 inches (10% chance of less than that)

Maximum amount, 0.80 inches (10% chance of more than that)1

Since the average of those two theoretical “extremes” dreamed up for this situation by yours truly is 0.425 inches, that’s my personal prediction for my house.   It helps, too, that I am the same person who will also measure the rain as well.

Will look, too, for a little ice in the rain toward the end of it as the temperature plummets after the cold front goes by.

So, what’s yours?  (Everyone should have a personal prediction.)

Yesterday’s clouds

Not much going on, mostly Cirrus, then Altostratus in the afternoon, that gray icy sheet that dimmed the sun so well.  However, there were a few flakes of Cirrocumulus.

7:41 AM. Kind of a mess. Some ancient contrail streaks, natural Cirrus, and some Cirrocumulus flakes (dark thin lines). Because the sun is low, Cc clouds can have shading, otherwise, no.
7:41 AM. Kind of a mess. Some ancient contrail streaks (streak in center), natural Cirrus, and some Cirrocumulus flakes (dark thin lines). Because the sun is low, Cc clouds can have shading, otherwise, no.
4:19 PM. Classic Altostratus clouds, deep icy ones with tops at CIrrus levels, typically 25-35 kft or so above sea level. Published meteorogists, looking at satellite imagery, often call this cloud "Cirrus." How funny is that? They do that because they see in the satellite imagery that the tops are cold, less than -40 C and don't realize that only a patchy type of Cirrus, spissatus, can have shading! How funny is that, again? But, here, my reader knows better than that!
4:19 PM. Classic Altostratus clouds, deep icy ones with tops at CIrrus levels, typically 25-35 kft or so above sea level. Published meteorogists, looking at satellite imagery, often call this cloud “Cirrus.” How funny is that? They do that because they see in the satellite imagery that the tops are cold, less than -40 C and don’t realize that only a patchy type of Cirrus, spissatus, can have shading! How funny is that, again? But, here, my reader knows better than that!

Enough fun for today….

The End

————————-

1Reluctantly, I remind the reader that the maximum rain amount seen for the last storm, 0.40 inches (10% chance of a greater amount), was laughable;  1.16 inches fell in Catalina/Sutherland Heights.  However, in formulating an excuse, CM would point out that the models didn’t see it coming either.

Reviewing our official weather symbols, the kinds seen on maps and stuff

While waiting for the next storm and watching harmless CIrrus and Altostratus clouds float by today,  I thought it would be good for you to review  our weather symbols,  weather “hieroglyphs,” if you will.  If you are a user of them already,  you know that they can make your weather/cloud diary more official looking, add luster to it.

If you have not seen these official symbols before, which are displayed below, it would be good for you to memorize and practice copying them down.  Since redundancy and repetition are the greatest tools in memorization, the symbols below are repeated several times; also so that you don’t skip over one.

As a practical hint, these weather symbols also make great design elements in wrought iron gates, doors, and fences for the truly weather-centric person!

A snap quiz next week will feature questions like, “Draw the symbol for a severe sandstorm”, or the one for sleet (frozen rain drops that bounce off the pavement, aka, “ice pellets”), and of course, a real favorite phenomenon here, one often discussed,  “Draw the symbol for drizzle.”  Remember, a symbol is worth a lot of words!

To make this review that bit more challenging, I have not included a legend that explains what each element below represents but maybe this link does.  Good luck!

Chartpak_001

 The stormy weather ahead

Still looking at a number of storms ahead, December 12-20th.  Here’s one, hot off the 00Z WRF-GFS model run based on global data from last evening, as rendered by IPS MeteoStar:

Valid at 5 PM AST, December 20th. Colored regions denote areas where the model thinks it has rained or snowed during the PRIOR 12 h. An arrow points to SE Arizona.
Valid at 5 PM AST, December 20th. Colored regions denote areas where the model thinks it has rained or snowed during the PRIOR 12 h. An arrow points to SE Arizona.

 

The End, symbolically, @

Big virga, but no drops here

Flash:  Plethora of storms lining up for Catalina  during the rest of December.  Spring wildflower seeds take note.  Expecting to see a little snow here, too, in one of those–happens about once a year at our elevation (3,000 to 3500 feet), btw, so its not terribly unusual.)

The first one, on December 12th, is in the bag, the one we’ve talked about for a few months I think (that forecast based on spaghetti), except now it happens on the 13th.  Droughty Cal will get slammed by this one, too.

Hope you’re happy now.

—————————————————————

Now, for the “main event,” a recapitulation yesterday’s clouds….

A Nice,cool and gray day it was, if you like sky-covering layers of Altostratus translucidus and opacus , interrupted in the mid-day hours by a lower layer of Altocumulus clouds.

Those Altocumulus clouds represented  a “thin” corridor of clouds between deeper bands that went over us yesterday.   Bands of thicker and thinner clouds are pretty normal as storms pass by us.  First, this overview from satellite of our cloud sequence:

Visible satellite image for 1:15 PM yesterday when Altocumulus clouds comprised the main deck, rather than Altostratus
Visible satellite image for 1:15 PM yesterday when Altocumulus clouds comprised the main deck, rather than Altostratus.  Too bad there was more humidity underneath this system,; coulda been a great rain.  The arrow points to our location and the thinner cloud corridor that pass over at that time.  Cloud banding like this always occurs with storms, providing lighter and heavier periods of rain over an hour or two.

From the beginning, these for your edification:

9:29 AM. Classic icy Altostratus translucidus. No droplet clouds evident. Hope you logged that remark.
9:29 AM. Classic icy Altostratus translucidus. No droplet clouds evident. Hope you logged that remark.  Estimated height above ground?  22, 000 feet at this time, somewhat lower than the balloon sounding indicated at 5 AM AST.  Stuff lowers with time as storms approach.

 

11:29 AM. Big virga rolls in from the horizon. Lots of weak radar echoes beginning to show up in our area.
11:29 AM. Big virga (falling snow)  from Altostratus opacus (sun’s possible  is not detectable  at this time)  rolls in from the horizon. Lots of weak radar echoes beginning to show up in our area. Some lower flakes of Altocumulus clouds can be seen at left center, and on the horizon, left center.  Bases now around 18,000-20, 000 feet above the ground.  Likely a few drops were reaching the ground where the virga hangs down another few thousand feet.  Freezing level was around 11,000 feet above sea level.
1:40 PM. Thin spot in satellite image, characterized by Altocumulus opacus clouds, now passing over our area between bands of heavy Altostratis with virga.
1:40 PM. Thin spot in satellite image, characterized by Altocumulus opacus clouds, was now  passing over us between bands of heavy Altostratus with virga.  As a CMJ, the appropriate thing to say to your neighbor would have  been, “Wow (lot of excitement here), what happened to those deep clouds?!  Cloud tops have really come down.  Must be a thin spot.  Hope  that darkness on the horizon is another deep cloud band because then it might rain.”  End of excitement.  Cloud bases as you would guess, have continued to lower (but not nearly as much as the tops did).  The Altocumulus bases here are estimated to be 12,000 feet above the ground.  (By the end of the day, they were about 9, 000 feet above the ground, 12,000 feet above sea level).

 

3:05 PM. That last banded feature in the sat image, consisting of Altostratus opacus again, is starting to pass overhead. More weak radar echoes were present, some passing overhead, but, saw no evidence of a single drop on trace detector (car parked out in the open, moved for that purpose, since CM can't be outside at all times.
3:05 PM. That last banded feature in the sat image, consisting of Altostratus opacus again, is starting to pass overhead. More weak radar echoes were present, some passing overhead, but, saw no evidence of a single drop on trace detector (car parked out in the open, moved for that purpose, since CM can’t be outside at all times.
3:06 PM. Most of you will share my excitement here; surely a drop will be felt at any moment! As you know, in these situations, the rain hits the ground (largest drops first) long after the preciping part of the cloud has passed overhead. So, here we are looking downwind over the Charoulou Gap at a bunch of virga that passed over a few minutes ago, hoping for that drop that never came.
3:06 PM. Most of you will share my excitement here; surely a drop will be felt at any moment! As you know, in these situations, the rain hits the ground (largest drops first) long after the preciping part of the cloud has passed overhead. So, here we are looking downwind over the Charoulou Gap at a bunch of virga that passed over a few minutes ago, hoping for that drop that never came.
5:01 PM. As the deep cloud tops moved away, and a large clearing approached from the west, the setting sun provided a golden view of Samaniego Ridge. The lower-topped Altocumulus clouds can be seen above Sam Ridge. Bases were now down to 9,000 feet above the ground. Tops were about 16, 000 ASL, about -13 C. Higher colder tops were still in the area producing virga.
5:01 PM. As the deep cloud tops moved away, and a large clearing approached from the west, the setting sun provided a golden view of Samaniego Ridge. The lower-topped Altocumulus clouds can be seen above Sam Ridge. Bases were now down to 9,000 feet above the ground. Tops were about 16, 000 ASL, about -13 C. Higher colder tops were still in the area producing virga.

 

5:03 PM. Even the teddy bear cholla, horrible as it is, can be quite gorgeous in the evening light.
5:03 PM. Even the teddy bear cholla, as horrible as it is, can be quite gorgeous in the evening light.
5:19 PM. Later, sunset occurred, pretty much on time. It was OK. These, of course, are those Altocumulus clouds, sans virga, too warm for ice production even with tops around -13 C, around 10 F.
5:19 PM. Later, sunset occurred, pretty much on time. It was OK. These, of course, are those Altocumulus clouds, sans virga;  too warm in this case for ice production even with tops around -13 C, or about 9 F.  Ice formation characteristics can vary from day to day, the reason is not always clear, but seems to be most closely related to the sizes of the cloud droplets.  The bigger they are, the higher the temperature at which they freeze.

Below, from Intellicast, folks who hate Accuweather, where our radar network thought it rained a few drops on you (or probably just above you) yesterday:

Radar-derived precipitation for the 24 h ending at 5 AM AST this morning. Note dry slot over Catalina.
Radar-derived precipitation for the 24 h ending at 5 AM AST this morning. Note dry slot over Catalina.

The End

 

Yesterday’s comet, space debris, or asteriod passage

There was quite an astrological event yesterday, hope you caught it. Only lasted a minute or two as a comet, or a gigantic piece of space debris, or maybe that asteroid that astronomers said was going to hit earth, an event usurped on the Seattle Times front page (!) by a Washington Husky basketball victory over the ranked Xavier U team1 blazed across the sky.

Happened to walk out side just as it appeared in the sky and became very afraid at first glance, but had enough presence of mind to take a couple of quick shots for posterity in the seconds before possible death as we all do these days no matter how bad things are for us at the time since we have our smart phones with us, and why not?  Might go viral and we’ll be famous at last!

I was thinking there would be this gigantic, cataclysmic explosion like the one that ended dinosaur life on earth 65 million years ago any moment.     But, then nothing happened and I realized I had been fooled by a parhelia (sun dog or mock sun) with a strong radial-like portion!  How funny izzat?  Here are more images of those things.

In case you missed it, or also got very afraid for a moment, likely as early peoples and their astrologers would have, likely interpreting the  phenomenon as a sign from the gods to sacrifice someone for a great crop or hunting season,  here it is:

2:56 PM. Rare comet or gigantic space debris sighting during the daylight hours.
2:56 PM. Rare comet or gigantic space debris sighting during the daylight hours.
2:56 PM. Zooming closer
2:56 PM. Zooming in closer
Also 2:56 PM. You can see how hot it is on the front end as it races across the sky.
Also 2:56 PM. You can see really how hot it is on the front end as it races across the
sky and into the earth’s atmosphere!

 The weather?

Oh, yeah.   Well first of all, it did rain during the Big Game in Santa Clara last night, as forecast here, and just about everywhere else as well, as many of you likely saw.   While its true that rain falls on the rich and the poor alike;  the good and the evil as well, it only rained Duck touchdowns on the Arizona fubball team last night.

How sad was that?

Was figuring an AZCat victory over The Duck would be the same as a Washington Husky one since we beat down the AZCats in every way imagineable except for the score when we (the former company team) played them a few weeks ago2.

Oh, yeah, the weather HERE….

Overcast pretty much the whole day in the State Winter Cloud of Arizona,  Altostratus–get a lot of that here as storms sideswipe the area.  As you know, Altostratus is a deep mostly or all ice cloud with tops nearly always up near where Cirrus clouds are.

Why, if its so friggin’ deep, you ask, is the optical depth nearly always less than FOUR?  (I can feel your anger).  Of course, more than FOUR would mean the sun’s position is not discernible; its just gray up there.  Well, my friend, its because Altostratus is mostly composed of ice crystals, not very high concentrations of them, typically a few to tens per liter, as contained in a volume of air in one of those today’s “Coke Tastes Great!”) liter bottles.  Those low concentrations let a lot of the sun’s light through even though the clouds are 2-3 km thick.  Really not much to As clouds if you’re flying in them, kind of like being in an extremely light snowstorm.  So, we can see where the sun is.  When the sun is gone, they”re likely more than a few km thick, maybe 4-6 km, since eventually even low concentrations of ice crystals won’t let the position of the sun be seen.

You can expect those thickest As clouds today at times.

Altocumulus clouds, all or mostly droplet clouds are surely going to show up, too, as the moist layers lower into temperatures that are too warm for all ice clouds.

Since droplets are 10 to 1000 times more numerous in clouds than ice crystals, and droplet clouds reflect more sunlight off their tops, a much thinner droplet can obscure the sun’s globe and look darker on the bottom than a much deeper ice cloud.  In techno-speak,  create its much easier for a droplet cloud to be associated with an optical depth of 4 or more– a great piece of information to pass along to your neighbors as a CMJ; do it in a casual way, it’ll be more impressive that way.

Since the 500 mb jet stream is passing south of us today, still looking for a few sprinkles or R– somewhere later this morning or in the afternoon around these parts.

The End, and its really enough! Yikes.  Storms still dead ahead in the remainder of December!

 

—————————–

1From the Seattle Times this classic front page on, The Importance of Asteroids Hitting Earth and Husky Basketball:

From 1997. Yeah, we save stuff.
From 1997. Yeah, we save stuff.

 

2Like all great former employees, I continue to root for the company team, even though have developed an AZCat partiality, as well.