here come the Santa Anas again


Crestline cam looks pretty interesting. Can clearly infer the dry desert winds are coming in and pushing out all the onshore stuff back toward the Pacific. Nice little battle in the sky, makes a neat picture. Double-switch day. Wonder if anyone flew?

I wonder in which direction (s)he landed. I just happened to see that on the Marshall Zoom image.

Rumor has it that it's still trapped in the shear layer and unable to land. Also, if you get into cloudbase on a Santa Ana day, you can hear the sound of its tattered sail as it flies by. 

Had the condor out yesterday evening when the north finally descended to the landing area. Descended isnt quite the word. Wind went from calm to 20 mph N in less than a minute. Slammed is more like it. Marcello, the student and I managed to rassle the thing and fold the A frame under and lay the thing flat then point the nose into the wind so it couldnt be whipped up into the wind.  Bagged the big thing finally and stuffed the straps and small stuff in the bag glad that it didnt go catapulting to the university. Wow. Spring.  The clouds that marked the convergence had been slowly getting pushed to the south. The switch was expected, just didnt expect it to be so violent.

  An un-countable number of times I've traveled from up on the mountain, where I live, down to San Berdoo, while the North winds were howling strong enough to blow my little car into the other lane.

  Then I'd find myself somewhere on Waterman Avenue, anywhere from 40th street on down to Hospitality Lane, and at some place along that route I'd see there was no wind at all, and quite frequently there would be a seabreeze from the South, usually with some Westerly component mixed in.

  I have always wondered: Where did that big mass of North wind go? Did it slide up over the seabreeze? Did the seabreeze and the North wind join forces and produce a huge up-draft?

  Unfortunately, my Scroogeness stopped me from stopping at the Stater Brothers store to buy a few helium ballons that I could release at various points along Waterman to hopefully reveal the answer to my question: Where in the hell does all that air go? I mean howling from the North and a half mile later a dead calm! How does that work? An inquiring mind wants to know!

  I'm betting that Ken Howells and Rob McKenzie know the answer ( why the "w" if we don't pronounce it?) and here's hoping they'll chime in and relieve my anxiety over this.

  It was fun seeing so many of you CSS'ers in the LZ last Saturday. Thanks for the compliments on my rubber powered airplane, she didn't fly too badly and was a lot of fun to fly. For me, flying is flying, whether it's a rubber-powered model or a hang glider. Trimming a free-flight model to get it's best performance is really very similar to shooting a perfect approach to a spot landing, or centering a thermal's core in one swift move, in that the satisfaction of successfully negotiating with an invisible medium, using a mechanical "toy", is a real treasure, one of many I've had over the years. Your Friend in Flight, Steve

I'm with Nate. It slides up over the sea breeze.  And not necessarily all that high up.

I grew up in Bloomington, staring into Cajon Pass.  I flew a lot of kites. And sometimes, the day after Santa Anas, I'd launch into a seabreeze, and as the kite got higher -- a hundred to two hundredish feet or so -- it would go all twitchy, then switch around from being east of me to being south of me. But I was still standing in a westerly wind.

So my theory is, on those days, both air masses were very stable. The boundary layer warmed and expanded (it was pretty generally a warm day), sucking in cool air from the ocean.  Eventually, that warmed air mixed with the offshore wind, making a sort of squished flat convection cell.

"Where did that big mass of North wind go? Did it slide up over the seabreeze?"

Yep. Indeed it comes in by sliding over the sea breeze. The colder air mass (sea breeze) will be on the bottom, with the front shaped vertically diagonally, sloping and lurching toward the Pacific. You could quantify this slope by looking at the gap between the Crestline switch time and AJX switch time; S\N switch gap was about 1 hour from the two WX's. Also need the relevant altitudes and distance, but those are given.

"Did the seabreeze and the North wind join forces and produce a huge up-draft?"

Heck yeah. Just look at those clouds in the photo I posted. Lot of vertical action going on there. Good thing Dan's Condor wasn't airborne on the training hill when it suddenly switched North. They might have overshot the LZ and ended up in the Channel Islands.