Like scientific opinion1, climate change happens. You may not know this, but only 15,000 to 20,000 years or so ago, a blink of an eye in light years, the earth was gripped by an Ice Age. No “hockey stick” handle back then! Snow and ice piled up over a kilometer deep on top of the Space Needle in Seattle. And the polar ice cap extended to places like Cahoga Falls, Ohio, while burying the Great Lakes, which didn’t exist.
NOW, of course, we’re in an “Interglacial” period called the Holocene, where its nice and toasty, for the most part, the way we like it as a people. Really, human beans do not like Ice Ages; they can really die off in a hurry2 and have to repopulate themselves afterwards! Well, I suppose that part might be fun.
The forecast models are foretelling something in the way of a flashback in the way of a pressure pattern over nearly ALL of North America that might well have been the average pressure pattern day after day during an Ice Age (there have been many), the last one, at its peak, not surprisingly, was called, “the Last Glacial Maximum.” I’d call it that, too.
Here are a coupla panels from the venerable Enviro Can computer model with its FOUR panels of weather. Take a look at the pressure patterns in the right side panels, you may have to use a magnifying glass, both showing the predicted sea level pressure pattern. These forecast maps are astounding to C-M and will, therefore, be likewise to you, too: a high pressure area so expansive with cold dense air that it covers millions of square miles, even more in square kilometers, maybe billions, since the kilometer is a smaller Euro unit of measurement that makes everything seem farther away when you’re driving to someplace and the distance is in Euros. (hahaha, just kidding folks).
So, we have an historical treat coming when the average temperatures every day in the US were 15-20 F lower during the Last Glacial Maximum! (Ugh.) The oceans were at lot smaller then, too, because a lot that water was piled up on top of the Space Needle, etc.
You might have noticed in these panels that the Ice Age-like conditions are plummeting rapidly southward, and big trough is starting to curl over the interior of the Pac NW. Yes, since we are still in the Trough Bowl, that curling air pattern, containing frigid air is headed toward Arizona, and will be here or not in early January.
Why a bifurcated statement?
Models are confused. Two model runs, only 6 h apart (5 PM and 11 PM AST last evening have the low center aloft for the SAME time, January 1st at 5 AM AST over a) Pebble Beach Golf Course, Carmel, CA; b) over Gallup, NM! How funny, outrageous, and frustrating is that? See below:
But, we are “gifted” with an opportunity to learn about chaos in the atmosphere, aren’t we, that is, those times when little errors can lead to huge differences in future states.
So, to resolve this weather conflict, and lose a few more readers, we go to the NOAA spaghetti factory, and examine the “Lorenz plot” for this time period and see which one is looney:
Well its pretty obvious that the goofy one is the one having the low over SFO and vicinity. Most of the circulation pattern has a center in Arizona somewhere. But this interpertation means that extremely cold air is likely to invade at least the northern half of Arizona as January begins. The good side is that there would be substantial, and later, reservoir filling snows in the mountains, and a good chance of substantial rain here in Catalina as the year begins.
The end of maybe solving a prognostic conundrum.
Well, its all “out there” by your favorite weathercaster, and they all do a pretty darn good job, and so no use hacking over what’s already known by everybody except to say that the jet streak at 18,000 feet (500 mb), that core that circumscribes precip from no precip areas during our winters, passes over Catalina (our area) around 5 PM AST according the latest model run.
And that’s, too, when the models expect the first rain around Catalina to arrive. As before, this ain’t gonna be too much unless we get real lucky, top amount likely below a quarter on an inch between 5 PM today and the end of possible showers later tomorrow afternoon.
And of course, there’ll be lots of wind, maybe gusts to 40 mph today, a windshift to the NW here when front goes by overnight, with a temperature drop of about 10 degrees almost simultaneously. Expect a frosty Lemmon on Friday morning when the clouds part.
You can follow today’s developments today best from IPS MeteoStar’s satellite and radar loop.
The interesting part is that echoes and clouds will appear out of nowhere as that big trough expands southward, cooling the air aloft, allowing cloud tops to rise to ice-forming levels. Also, if you go there now, you will see giant clear slots between those middle and high clouds that passed over last evening until right now (Ac castellanus visible to SSW now), and a tiny band in west central Arizona, and the echo-producing clouds in the NW part of the State. Those unstable-loooking clouds will be gone soon.; they’re more from tropical locations.
Keep an eye on that little band in the middle; it may turn into a bona fide rainband as clouds add onto it, widens and thickens. That’s probably what’s going to bop us this evening with rain.
Expecting to see a nice lenticular cloud downstream from the Catalinas today. They’re common AHEAD of the jet core since the air is much more stable then, resists lifting and so you get cloud pancakes that hover over the same spot. How you log them if you see any.
Will we see our usual, “clearing before the storm”? This is when middle and high clouds depart, there’s a big clearing followed by an inrush of low, precipitating clouds. Not sure, but will look for it if that little band of middle clouds ends up as only that as it passes by today. The invasion of low clouds would follow that. Too much speculating today!
Finally, the End. I’m sure you’re glad, too, if you got this far!
1Remmeber back in the late 1960s and early 1970s when it was widely believed that a new ice age may be at hand because the earth had been cooling off for a coupla decades? It was also being pointed out that an ice age could onset in a hundred to a few hundred years from past ice age onsets! Yikes. Scary times on earth then when the Beatles were popular.
2Of course, if you were to die in an Ice Age, you might end up being well-preserved and then people would see what you looked like, the hair style you had, tattoos, etc, as we’ve seen with a few dead people that have been found from those glacial times. I guess that’s something positive to say about cold times.