Grandson of “Frankenstorm” knocking on Heaven’s door (Catalina, Arizona)

Well, I think Catalina, AZ,  being next to the Catalinas, is “Heaven’s door”.   I think, too, to have a second consecutive thought,  that we’ll get more than an inch out of this Big Boy which is rare here in Catalina for a storm in the wintertime.  Not close in areal extent to the original “Frankenstorm” that struck the West Coast in January 2010 with record setting low pressure, but a potent one anyway.   In the January 2010 storm we received 1.41 inches the first day and 1.18 inches the second to “ice” a fabulous wildflower bloom that year.  We sure seem headed to a fabulous bloom season this year, too.

BTW, there has been a lot of rain in droughty Texas.   We are brothers/sisters in drought relief it seems these days.  How nice; adds to the holiday cheer.  Maybe the price of hay will go down..  It seemed interesting to throw something about Texas in there.  Here is a map showing that great TX rain of yesterday from WSI Intellicast1.  These radar-derived amounts precipitation are pretty much spot on–I’ve checked ground gages a number of times.  We should be seeing “green”,  1-2 inches) over much of AZ in the next couple of days, too.  So, the map below is like a preview for AZ.

Speaking of green, look at the “green-for-rain” in AZ in the lower right hand panel of this forecast for this afternoon ending at 5 PM MST.  During the prior 12 h, beginning at 5 AM MST, the entire State of AZ is virtually covered.   I am just beside myself when I see a map like this!  And look how far to the south of Baja California the circulation of the storm extends.  Its gorgeous to see this.   I guess there could be some flooding here and there, and some “snow birds” might complain about the “crummy AZ weather”, but….you can find people who will complain about anything.  See the whole wonderful model sequence of rain and mayhem in AZ here, and in much more detail from the U of A weather department, here.

Look, too, at how excited the National Weather Service, Tucson is!  They must have 50 bulletins out–be sure to keep reading them.  They are really having a lot of “fun” down there, too.

Late breaking storm bulletin:  We have sprinkles in the area (0425 LST).  Check this radar-cloud map out from IPS Meteostar.  What a great day this is going to be!  Enjoy.   Good chance we’ll see water in the CDO and Sutherland Washes, and maybe some snow mixed in with the rain as the storm closes out Tuesday evening now.

But is this storm the end of our “fun” weather?  Oh, no, my friend.  Another cut off low develops in our area after speeding down as a trough out of the NW in five days.   Another round of significant rain is likely, though not as much as this one.

Some cloud notes from yesterday, including some chat about the unusual streaks.

In that warm afternoon yesterday, it was so great seeing sheets of Cirrus and Altostratus (ice clouds, Altostratus with heavy shading) massing on the horizon, knowing that this time it was NOT just going to be a sky decoration for a nice sunset, but were clouds filled with stormy portent. You probably noticed the lack of sunset color due to the extensive coverage of those clouds upwind. No break allowed the sun to under light them, a sign of extensive clouds upwind to the southwest.

Also, unless you were blind you saw some unusual events in the thin Altocumulus (translucidus) layer yesterday: ice canals and splotches of ice produced by aircraft that flew in them. When so many happen as did yesterday mid-day, its a good bet those Altocumulus clouds, though comprised of liquid droplets, are terribly cold. While the TUS morning sounding did not pick up this mid-day layer, one can be confident that it was likely colder than -20 C or -4 F.

What you also saw was examples of how the presence of ice within a droplet cloud, causes the droplets to evaporate, and the ice crystals to grow and fallout, something that happens on our rain days. However, because there were so many ice cyrstals produced by these aircraft (almost certainly all jets) they compete for the tiny amount of water available at -20 C and form small crystals with little fall velocity.

So the trails of precipitation are very fine and don’t go very far. Here are some examples of that rare phenomenon, rare because for us to see it, takes a thin, cold water droplet cloud, and it has to be high enough so that aircraft are frequently penetrating it. One wonders why, in some of these cases, the trails yesterday were so long with an aircraft probably could have climbed or descended a couple of hundred feet to avoid flying in a light icing producing cloud (the Altocumulus layer composed of supercooled droplets)?  Note “ice optics” in ice canal in the first photo, a weak sun dog so I didn’t just make it up that the canal was ice.  I you wanna know more about this phenomenon, go here and/or here.