Why Zapata?

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 I collect some articles here that explain the special nature of Zapata. Some of them could be just linked, but I seem to be spending more and more time on just fixing links...
Article by:   Davis Straub (ozreport.com)     at:      http://www.davisstraub.com/WRE/whyzapata.htm

Why Zapata?

Strong winds, cooler moist air over a hot desert, large high pressure to the east which creates winds in a consistent direction for a distance long enough to set sailplane records, mechanical lift from gradually rising terrain to the north with a southerly wind, streeting at 9 AM with cu's forming before sun rise, early starts for long days, strong lift during the middle hours over the hill country, consistent very good conditions day after day when the normal weather pattern sets up.

Gary Osoba has been studying the weather patterns over southern Texas for a number of years. He has found that the Bermuda high sets up in the Gulf of Mexico and stays there for a couple of months. When it's sitting to the south of the southern tip of Texas, the winds on its west side are from the south straight up the state of Texas. The high is so big, that the circular flowing winds are essentially going in one direction, north, for the length of a hang glider flight (under 500 miles).

These winds circulating around the high are bringing in cooler moister air from the Gulf and pushing it over the hot dry Texas alluvial plane north of the Rio Grande. This cooler air, a few thousand feet thick, is cooler than the desert even at night. Even as the desert radiates its heat back into the clear sky, it is often still hotter than the cool air coming up from the Gulf. Sometimes, in the early morning, clouds will form at 1,000' completely covering the area around Zapata. They will break up around 9 AM, forming streets of cumulus clouds. Streets formed by the winds.

The winds can be strong, 20 mph on the ground and 30 to 40 mph up high. These winds are fed by the strong high pressure over the Gulf. To set world records, you need strong winds to go along with the moderate to strong lift. The winds provide the push, as well as the cool air, which provides the initial lapse rate.

To be able to stay up in the early morning relatively weak lift, before the desert floor is heated up by the sun, you need cu's to see the lift, and streeting to see the lift lines. You need streeting to follow the general direction of your flight so that you can get a fair distance even when the lift is weak.

After the first inversion is broken (when the desert floor has heated up the air below it), and the first lower cu's disappear, you need the second set of cu's to form, and to be set up in streets by the winds. You've got be able to get high enough in the first cu's to be able to stay off the deck while the lift goes from everywhere and weak, to sparse and moderate.

Around noon the cloud base will rise from 2 to 3,000' to 5,000'. The lift will increase in strength and lift sources will be more widely scattered. With streeting you will be able to get under the streets and concentrate on distance and not worry so much about height.

Article by:   Davis Straub at: one of the ozreport.com newsletters Summer 2005       

Where else would we go?

That's what Gary Osoba answered when I was lamenting about the two hurricanes, one tropical storm and the front that came through Texas this year during our two week only WRE. He couldn't think of another spot on earth with a weather feature big enough to allow him to fly the Alisport Silent 2 over 801 miles in a straight line.

As I write these words, I think about all I have written and done to try to illustrate the magic that you can find in June and July (August, too) in south Texas, for those ever so few of you who really want and are ready to go for the Ultra Marathon of cross country hang gliding. Does it make an impression at all? Does anyone outside a very small set of folks get it? Well, maybe they just don't care.

Oh, so you think that there really is a better place on earth for the Ultra Marathon? Some place here where you regularly fly? Really? Just how many world records have been set at your favorite spot?

Have I said before (more than a dozen times) that it's the wind? The wind makes all the difference, especially in my morale and attitude. When I'm flying over the ground at 60 mph when gliding, when I can easily get to clouds that are so far away, when I see that I can make it easily to the next available landing area, when there are so few at first, I just want to continue to ride the wind. Where else?

And what about that early morning launch, the one that provokes so much anxiety before launch, then becomes a game of staying up in anything while drifting over the lands behind locked gates. But there's the ten mile glide above the clouds and already you are almost at the first public road as you finally get low enough to come in under a solid cu. There's the fact that you can launch before 9 AM at all. There's the tow to the east that makes it easy to get around the airspace 40 miles away, an hour later. There's the fact that as the morning progresses (even in the first hour) the cloud base rises and the thermals gain strength. Where else?

What about that early morning wide spread lift? What about a day full of light sink when you are not in lift? What about being able to stay up over the most shaded ground? Where else?

Then there is the ride up the highway as the cloud base rises and the clouds begin to street up. There are even cu's underneath cirrus. Every one of these cu's is producing. The land is rising up slowly and the cloud base rises as the morning progresses and if you are very good and started early you can have 100 miles by noon. Where else?

The country side opens up and the anxiety related to making sure you've got a good landing area within glide is relaxed, as you find yourself 170 miles out, and getting into the hot rocks of the hill country where the land rises up abruptly as does the cloud base. You can follow up a valley that cuts through the hill country and provides plenty of safe landing areas. Where else?

The wind has been blowing and it has been blowing straight for hundreds of miles and now it is going to keep blowing straight to the north for many more hundreds of miles as you get up on the Edwards plateau and the cloud base rises to 6,000' AGL to 9,000' AGL. On many days the streets are lined up and you just stay in the streets. Where else?

In this farm and ranch country you have plenty of roads and it's easy to land anywhere as the sun goes down between 9 and 9:30 (10 to 12 hours after you started). You've got an extra half hour if you've brought your strobe light. Be sure to stay out of the minimal airspace at Lubbock. Where else?

So, just where else on earth do all these things come together?

Two years (2000 and 2001) of stellar conditions, where 200 miles was a failed flight, one that you cut short so that you can get back and try again on the next day. The next year, the nine year drought ends, and we get two good days and four world records. In 2003, a hurricane and no good days. In 2004, it's still wet, and we get a good week with wet ground conditions and two world records.

In 2005, as above. Three world records before the second hurricane. One 200+ and one 365 mile flight on the last good day. Three good days (none as good as the first two years).

Have I made my case? You be the judge.

Okay, how about way northern Australia (Hughenden, Queensland, Australia) in April? Does the wind blow out of the east at 15 to 20 knots every day? And will that make up the limited day length in the autumn? Look it up on Google Earth. Follow the road west.

Article by:   Davis Straub at: http://www.davisstraub.com/Glide/zapataweather.htm    

World Record Weather

This page is the best of them all about the weather conditions in Texas.
It is too long (and I don't mean to break copyrights) -> hope it stays at the link you see above!