Light rain showers overnight, just before midnight, and again just after 1 AM AST, raised our Sutherland Heights storm total to 0.33 inches, decent but disappointing in view of model and personal expectations (0.60 inches).
What was especially interesting is that those nighttime light showers didn’t show up on the TUS radar, suggesting very shallow tops, perhaps a “warm rain” event, one not having ice, or an “ice multiplication” event with tops warmer than -10° C, about where the tops were on the 5 PM AST TUS sounding.
By this morning, the tops were barely below freezing (about -3° C). Don’t expect to see ice today, except at Cirrus levels!
Last of the Cal rain blasters is making its way across the State today, with another 5-10 inches expected in favored Sierra and coastal ranges in the next 24-36 h. Numerous sites north of SFO have now logged over 100 inches since October 1st! Imagine. Great to see that Cal drought vanquished in a single year, so unexpected. Let’s hope the Oroville Dam, N of Sacto, holds.
PS: Using point and shoot cam now with “real” camera in the shop for awhile.
That’s why you come here, to answer important questions like that. After all, those precipitating clouds could have been Nimbostratus, Stratocumulus opacus praecipitatio, Cumulonimbus capillatus incus flammagenitus, or even just “plain” Cumulonimbus capillatus (no anvil), and possibly, Stratus opacus nebulosos praecipitatio.
Of course, with no large fires around, we can at once rule out Cumulonimbus capillatus incus flammagenitus….(the new name for clouds on top of fires, formerly referred to by the more accessible terms, “pyrocumulus” or “pyrocumulonimbus.”
For the curious, and since I broke my camera and don’t have the dozens upon dozens of photos to regale or bore you with, I will reach into the archives for a shot of “flammagenitus” and show you one from the pyromaniacs’ paradise, Brazil!:
Now, on to more recently viewed clouds, like yesterday’s:
Later these scenes were overtaken by a slab of Nimbostratus and steady light rain for a few hours.
A note on the recent southern Cal rain blast
As you know, up ten inches fell in some mountain locations in southern California as a monster low pressure system smashed into the coast near San Francisco1. You might recall, too, that the shift of the jet stream (and thus storm track) into the southern portions of California was well predicted two weeks in advance in those crazy spaghetti plots. You can’t always get much out of those plots except maybe the degree of uncertainty in weather patterns a couple of weeks out, but that was a rare case in which the signal far upstream for something strong barging into southern Cal also strong. And, of course, we are experiencing the residual of that storm, also as was indicated in those plots (“…the weather change around the 18th.”
Presently, a another sequence of extremely heavy rain is in the pipeline for central and northern California starting today, which will take a few days for it to come to an end.
Following a break, what was intriguing in the model outputs, and a little scary was that it appeared that yet another scoop of tropical air was going to jet across the Pacific under another blocking high in the Arctic and Gulf of Alaska into California. Take a look at this prog:
Here’s where spaghetti can shed some real light:
So while it is still possible that some model runs will indicate a blast from the sub-tropics affecting Cal, they can be pretty much waived off as outliers (not impossible “solutions” but rather unlikely ones. Breath easier Califs! At least after the current onslaught ends.
BTW, can you see what kind of weather is indicated in this plot for the SW and old Arizony?
Cold; temperatures below normal, precip likely at times.
——————————– 1The low pressure center that passed over San Francisco yesterday was not as deep (988 millibars) as the notorious “Frankenstormmaggedon” of 2010 which barged into Frisco with a 979 millibar center. You may recall, too, that spaghetti had strongly suggested a “Frankenstormaggedon”, as it was later called, also more than ten days in advance. Recall, too, if you can recall, that 2009-10 was an El Niño winter with this kind of thing pretty much anticipated.
For history buffs, I reprise that January 2010 storm as seen on our national weather map. You may recall that, if there’s anything left in that noggin up there, that Catalina experience no less than THREE inches of rain as this system went by, taking a couple of days:
Well, it will be pretty obvious, ludicrously so to spaghetti lovers, the sequence shown below. It goes from “warm in the West (again); cold in the East pattern to another undercutting flow from the Pacific, the kind we’re having right now under the “soft underbelly” of a big blocking high, except that the tropical flow from the Pac this time is a little too far to the north to give us anything.
But, it will be another floody situation for northern Cal in the coming days. Some places, mainly north of “Frisco”, have already picked up 4-6 inches in the first blast which hit yesterday. Ten to 20 inches more is likely over the next week at favored locations. Having quite the water year there, really a lot of water year.
You may recall that the current situation, alluded to in the “break on through to the other side” refrain used here about ten times, was well predicted about two weeks in advance! That’s what spaghetti can do for you!
OK, enough jabbering, let us move on to the current exciting examples that popped out from last night’s global data ( there are outputs after adding little errors at the start of the model run, to see how the flow is changed with them in it. Sounds crazy, I suppose, but is considered a huge advance in forecasting, a stupendous tool, that is, to make errors in models at the beginning of the run). Heck, they even do that in climate models that simulate 30-50 years from now, and you’d be amazed at how the tiniest fraction of a degree change the beginning makes (see Deser et al 2012).
Well, the first one’s not so exciting since we’re dry and hot for this time of the year, and its a common one that can get stuck for weeks at a time, so you REALLY hate to see models project a bulging ridge poking north along the West Coast. It could mean a rainless February here, if it persisted.
Here’s the exciting follow up, though, pretty unexpected given the above, showing a sudden collapse of the West Coast ridge regime, and strongly suggesting that wet spell has begun in Arizona, including regions of Catalina and Saddlebrooke:
So, you’ll want to get outdoor work done before this.
Historical note of interest, added value content, etc.
Some of you may remember that the 564 decameter contour (those red lines) at this level (500 millibars or around 18,000 feet above sea level on average) was used in the early years of forecasting before computer models (50s and early 60s) by southern California forecasters to demarcate where rain would fall in California–at and north of where that 564 decameter contour intersected the coast when upper troughs came in. The Old Forecaster remembers, though not much else…
So those red lines barging into southern Cal after a LONG fetch from the subtropical Pacific in the plot above mean central and southern Califs better watch out for some major rains a little before we ourselves get a dousing around the 18th of Feb.
Isn’t it great what spaghetti can do, that is, constrain our future weather to fairly certain outcomes two weeks in advance!
There was a sunset yesterday, btw:
Upper level snow flurry passes south of Tucson! Trying to generate some excitement here….
Since we have nothing better to do for quite a dry while here in AZ, and CMP is from southern Cal, where he kept a weather and a cloud diary1 and played baseball2, here’s the latest on the Cal drought we’ve heard so much about, below, from the Drought Monitor folks at the University of Lincoln Cornhuskies University as of January 24th.
Added to this map is a couple of rainfall totals in the drought affected regions from January 1st through the 23rd, 2017 (i.e., only partial monthly totals) from the CNRFC, a superb site, btw:
Well, as you can see, it takes India monsoon caliber rains3 to end drought completely in California. Or, maybe the DM folks are just a little behind; could be. Avalanche hazards have been moderate to “extreme” during this period due to the tens of feet of snow that have fallen in the Sierras. Yay for California water supplies THIS water year!
Here is a table of the top 20 rain totals through January 23rd from the CNRFC:
————————————– 1Perhaps you don’t believe me that I kept a weather and cloud diary growing up. Here a report from the San Fernando Valley:
3Rainfall totals can be over 100 inches a month at the monsoon’s peak in India. The record is 366 inches in ONE MONTH at Cherrapunji in the NE corner of India in the Assam region. Of course, CMP must go there; its on the “bucket list.”
One passed over at 9:19 AM with a hard multi-second, surprise rain shower. One person reported a couple of graupel, or soft hail particles. Tipped the bucket, too; 0.01 added to our Sutherland Heights storm total. Its now at 0.23 inches. Of course, there was no damage, but putting that word in a title might draw “damage trollers”, increase blog hits….
The rest of the day was clouds withering, getting mashed down on tops as bases rose and tops settled back, then suddenly, about 3:30 PM, small areas of ice crystals began to show up in a couple of spots, and, boy, did things take off after that. Tops were lifting to higher temperatures, likely due to an approaching trough, one that otherwise is too dry to do much else.
Honest to goodness cold, wintertime Cumulonimbus clouds formed, though not very deep ones. Probably of the order of 2-3 km thick is all (eyeball estimate).
But with our cold air aloft, tops were well below -20° C (4° F), lots of ice formed in them and produced streamers of ice and virga across the sky, and in tiny areas, the precip got to the ground.
And with “partly cloudy” conditions, there were lots of gorgeous, highlighted scenes around the mountains.
Let us review yesterday’s clouds and weather and not think about the future too much, starting with an afternoon balloon sounding temperature and dew point profile from IPS MeteoStar:
So what do clouds look like when they have tops as cold as -28°Ç?
Well, I really didn’t get a good profile shot of those clouds, they were either too close, obscured by other clouds, or too faraway, so instead let us look at two dogs looking at something as a distraction:
Well, let’s start this when the ice first appeared in a cloud, much later in time than what was thought here yesterday morning. If you logged this “first ice” you are worthy of a merit, a star on your baseball cap:
Well, while flawed from a cloud profile sense, here’s what they were looking at, it was the best I could do:
Let us go zooming:
Looking elsewhere, there are snow showers everywhere!
The day concluded with a very nice sunset:
Now, the long dry spell… Break through flow from the Pacific under the “blocking high” eventually happens about a week away now, but more and more looks like that flow might stay too far to the north of us, rather blast northern Cal some more, and not bring precip this far south. The blocking high needs to be in the Gulf of AK, but now is being foretold to be much farther north…
The End, gasping for air here. More like a treatise than a quick read!
I guess “billows” (“undulatus” in cloudspeak) two days ago in the late afternoon wasn’t enough of a sign that the weather was changing. Yesterday we had fast moving Cirrocumulus with rainbows in it, and as the sun was setting, “jet streak Cirrus”, a line of Cirrus clouds often seen in the very core of high altitude, powerful jet streams passed overhead.
How hard was the wind blowing up there in that Cirrus last evening? Oh, our Tuscon balloon sounding, lifting off around 3:30 PM, going up about a 1000 feet a minute to, indicates that the max wind up there at Cirrus level was 146 knots (just under 170 mph)! Yikes. Poor balloon. Must be in France by now.
The storm has been a bit of a disappointment in rain production. We’ve only logged 0.22 inches1. Not as much as foretold here, 0.33 inches, but that forecast was a better prediction than by “Weather Underground Robotics” (0.58 inches). Its great to beat a robot!
We had another sign yesterday in the fastest moving Cirrocumulus clouds I think you’ll ever see around here (about 100 mph), ones at just 18,000 feet above sea level, 15 kft above Catalina: rainbows of color near the sun called iridescence (also called “irisation”). Here, as is the norm here, are a few too many shots of the same thing2.
The colors themselves, of course, don’t warn of something about to happen, but the fast movement from the southwest did; a powerful jet stream is over you. That strong stream, the result of temperature gradients in the atmosphere, is dividing deep warm air from deep cold air, and steers the alternations of high and low pressure centers, and with those alternations of lows and highs along the jet stream, air is drawn from different latitude zones and the boundaries where those different masses of air meet at the surface, is called fronts. Here, such as last night, its nearly always cold ones.
The rest of the day was pretty exciting, the wind arising suddenly yesterday morning, along with our usual great visibility, and darker blue wintertime skies, made the clouds stand out more.
The sky at last, considering the power of the trough approaching, FINALLY began to fill in. Started looking around for the first sign of ice having formed in these clouds as the air aloft became cooler. Along with this filling in by Cumulus and Stratocumulus clouds, some sun highlights began to appear on our mountains, contrasted by the darkening skies above.
Eventually our jet streak Cirrus provided the background for another great sunset scene:
Today’s clouds and weather
From that map above, you’ll see that there’s a “tail-dragger” trough still to the west of us and about over Sandy Ego (haha). That’s going to keep the air over us extremely cold, and with some sun, the Cumulus clouds that arrive are expected to have tops colder than -15 to -20° C, plenty cold enough for the formation of ice.
Ice means precip, snow up there, rain down here in spots. So, we could still pick up a few more hundredths if a shower happens to drop by. The chance of isolated very light showers in the area is 100%, but no one can tell you if one will actually land on us. You’ll have to be watching, mostly after 12 noon. Look to the west toward the Tortolita Mountains, terrain that ought to spawn one or two of those.
Looks like a longer dry spell ahead; several days to a week, maybe more.
1CoCoRahs gauge, btw. NWS-style gauge had only 0.20 inches, likely due to enhanced wind loss associated with my collapsing prickly pear protector. 2 I was driving and had to park and jump out of car to get these. You only have seconds or maybe a minute or three to capture stuff like this.
To educate you on how bad this is, why just yesterday, based on the SAME model but a different set of global data, the model said we would have, 0.59 inches. So, its already changing our forecast, diminishing it! How bad is that?
The problem with those forecasts is that they are heavy with “objectivity”; there is no human intervention. Its the work of a robot of sorts. And we know what robots are doing to the economy and jobs.
Here, straight from a human heart, we had a forecast of 0.33 inches total from this storm, one laden with emotion and often based on wishful thinking when large amounts are forecast. They’re often, based, too, on pattern recognition (“looks like that storm that brought us that much last time, or look where the core of the jet stream is!”)1
That forecast of 0.33 inches in the gauges right here in Sutherland Heights is not going to change just because some new data came in!
So, which one do you want? A forecast that yo-yos every few hours as demonstrated by the Weather Underground one? Or one that stands tall against new data?
I think the answer is obvious.
OK, enough about “robots” and weather; on to yesterday’s afternoon billows:
Well, there you have it, another tediuous contribution from the CMP.
The End here, but the beginning of the next storm!
———————————– 1Analogs to previous weather patterns are also part of the forecasting arsenal used by computers and other forecasters these days.
A few more hundredths fell after 7 AM yesterday, boosting our storm total to a remarkable 1.42 inches, January now about twice our long-term average.
Here’s what all that precip did to our beloved Cañada del Oro Wash:
After a few more hundredths of rain, the skies broke open, and as we know well, some of our most spectacular scenes occur under deep blue skies punctuated by puffy Cumulus clouds, shadows and highlights on our now snow-capped Catalina Mountains.
In the meantime, more highlights on Sam Ridge:
Finally, that incredible sunset afterglow on our mountains:
Oops, oh yeah, storm tomorrow, supposed to begin in mid-day to afternoon hours. Looks like a third of an incher. Also looks to be a bit colder than the last storm, may see a flake or two by Tuesday morning.
In case you don’t believe me that over an inch fell, this digital record from Sutherland Heights with writing on it:
Probably a little more to come, too. Got some blow damage, I’m sure. Will be looking for roof shingles around the yard today.
And, as everyone knows from their favorite TEEVEE weatherperson, “New Storm to Pound SE Arizonans!” Begins Monday night, Tuesday AM. May have snow in it as it ends.
Your know, its no fun telling people what they already know, so lets look ahead beyond the normal forecast period of great accuracy, beyond not seven days, not eight, but beyond TEN days!
First, we set the stage with a ten day look ahead (from last evening) in a NOAA spaghetti factory plot:
This plot indicates that the pattern of a towering, storm-blocking ridge is certain along the West Coast by ten days–will be developing for a day or three before this, That ridge represents an extrusion of warm air aloft over the entire West Coast extending all the way into Alaska. The couple of red lines in and south of AZ are due to the change of a minor, likely dry, cutoff low in our area about this time (plus or minus a day).
In other words, this plot suggests a warmer, dry period develops over AZ, and storms are shunted from the Pacific Ocean, located west of the West Coast, all the way to Anchorage and vicinity, They will be welcoming a warm up in weather up thataway at some point in this pattern.
Is that it, then, for the AZ winter precip? It could happen. Just one more storm after the current one fades away today?
Hint: Sometimes anticyclone ridges like the one in the plot above get too big for their britches, and fall away, or, break off like a balloon from a tether, and a warm blob of air aloft sits at higher latitudes, often floating off to the northwest.
The exciting ramification of this latter scenario is that in the “soft underbelly” of the “blocking anticyclone” (as in American football), the jet stream throws something of a screen pass, goes underneath the belly of the blocking high, and races in toward the West Coast at lower latitudes. Having done so, such a break through pattern (“Break on through to the Other Side”) results in heavy rains in Cal and the Southwest.
Izzat what’s going to happen?
Let us look farther ahead, unprofessionally, really, and see if there is evidence in spaghetti for such a development and you already know that there must be because it would explain why I am writing so much here. Below, the EXCITING spaghetti plot strongly indicating break through flow breaking on through to the other side, i.e., the West Coast, from the lower latitudes of the Pacific:
Well, we’ll see in a coupla weeks if CMP knows what he is talking about.. I think this is going to happen, resembles what’s happening now, and weather patterns like to repeat, more so within the same winter. However, how much precip comes with this pattern will be determined by how much flow breaks on through to the other side….
Let us begin our look at yesterday’s clouds by looking back three days ago before the Big Storm. We had a nice sunrise. Here it is in case you missed it:
Moving forward to only two days ago, the day preceding the nighttime blast: a cold, windy day with low overcast skies all day, shallow, drizzle-producing clouds, something we don’t see a lot of here in Arizona.
By the end of the day, the clouds had lowered again, and we were about to have a very interesting night!
———————- 1Remember how great we hippie relics thought that first Doors album was? Later, the Doors, and that era were to be made fun of by 80s punk and humor group, The Dead Milkman in “Bitchin’ Comaro.” (Its worth a listen.)