Spinning on down from Glasgow to Rocky Point, a low

This is pretty interesting; don’t see this happen too often where a lobe of low breaks off and spins from Montana, back toward the south-southwest to pretty much over Rocky Point, MX, as you will see in this past 48 h water vapor loop.  In a water vapor loop, you pretty much see all that the movement that is taking place in the atmosphere and here you can begin to understand why it takes biggest computers on earth to model it.  Here’s a close up from IPS Meteostar.

Note, too, those white puffs exploding in west Texas as our little low spins thisaway.  Those are massive thunderstorms that our low has and will be triggering in west Texas and eastern New Mexico over the next few days.  This is great to see that happening due to the drought those poor folks have been experiencing over the past couple of years.  This little low, as tiny as it is, will make a huge dent in those conditions in some areas.  It really would be great to be there in some little town, like the well-named town of “Plains”, TX, and see how happy the folks are getting as the rains hit.  It would be like the end of a Hallmark movie where everyone is quite happy about how things have turned out.

Here are two shots showing what its like now in Plains-Floydada, TX, area,  First, you can see that the earth is quite flat there.

Note green along highway. It has been raining off and on in these areas for the past month, so things are perking up. There were occasional bursts of wildflowers, too.
These aren't horses. What are they?

But while Texans are getting happier and happier (and I hope they don’t complain about flooding because that would be just plain WRONG), what’s in it for us?

Well, the quality of moisture is less here toward the center of the low, maybe about 1/3 as much in the air over us as in Texas.  So, what does that mean we will see?  Maybe a few Altocumulus in streaks, maybe finely patterned Cirrocumulus, and then as afternoon comes on, some Cumulus with high bases because its so dang dry.  I better predict some Cirrus cuz I see some now!  Also, I think I will forecast that the low temperature this morning will be about 62 F here in Catalina because that’s what it is now.   Maybe some ice optics, too, now in progress!  Continuing, these clouds, too, mean some great opportunities for sunrise/sunset color and ice optics now that I see one (parhelia).

But with those high bases goes low temperatures, likely well below freezing, and you know what that means.  The tops are likely to be colder than -10 C to -15 C, 14 F- to 5 F), an ice-forming threshold hereabouts for small, high based Cumulus.   With the formation of ice, VIRGA, snowflakes and ice crystals come out the bottom.   You can see this by the hazy look around the clouds where it is evaporating–ice takes longer to evaporate.

In the higher terrain, the virga will melt into rain and reach the ground, and the clouds will likely get tall enough to produce lightning, but not here today, but to the north of us at least early in the afternoon and evening.  Our best chance of rain with thunderstorms in southeast AZ will be tomorrow as the moisture gradually increases over us from the backflow around the north of the low.  The low is forecast to pass to the south of us tomorrow and Thursday.  You can see all this happening in our local U of AZ weather model here.  (Note the local time is in the upper left hand corner.  You will see the precip is only forecast to occur in the afternoon and evenings with this system.

So, finally, some weather excitement in the offing!