Jesse- was it you that mentioned the Skew-T's?

T

Tracey

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tracey
Don't those only take readings 2x a day? If that's the case- why do you find them more helpful? (This question sounds as if I'm disagreeing with you-- if it was indeed you that said this! For the record, I'm not, I'm trying to learn and see another way of getting wind info).

Thanks...
 
I'm curious too, I never got an answer in the earlier thread about just what folks should use instead of the winds aloft product.
 
TMetzinger said:
I'm curious too, I never got an answer in the earlier thread about just what folks should use instead of the winds aloft product.
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That's why I'm wondering, I know that Skew-T's will take a wind reading all the way up, but they're only accurate (as far as I know, could be wrong) 2x a day.
 
If you're using the Skew-Ts for wind only, then you're not really putting them to their full effect.

Sure, you can get winds. But what's more valuable is you can see where the freezing level is, where clouds are expected to be (including layers that you may be in between), and figure out potential threats such as icing, and generally plan an IFR flight.

Yes, it's for one location and if that location isn't one of the ones where they send up a weather balloon it's simply a forecast, but if you check multiple sites, it can give you a broader picture. I also find the forecast to be pretty accurate.

If all I'm concerned with is winds, though, I'll typically use the graphical winds aloft product. Makes it easier for me to see what to expect.
 
Ted DuPuis said:
but if you check multiple sites, it can give you a broader picture. I also find the forecast to be pretty accurate.

If all I'm concerned with is winds, though, I'll typically use the graphical winds aloft product. Makes it easier for me to see what to expect.
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Thanks. Checking multiple sites of Skew-T's could be very valuable... you can probably get a good sense of how wx is progressing. Where do you get the graphical winds aloft info?
 
Ted DuPuis said:
If you're using the Skew-Ts for wind only, then you're not really putting them to their full effect.

Sure, you can get winds. But what's more valuable is you can see where the freezing level is, where clouds are expected to be (including layers that you may be in between), and figure out potential threats such as icing, and generally plan an IFR flight.

Yes, it's for one location and if that location isn't one of the ones where they send up a weather balloon it's simply a forecast, but if you check multiple sites, it can give you a broader picture. I also find the forecast to be pretty accurate.

If all I'm concerned with is winds, though, I'll typically use the graphical winds aloft product. Makes it easier for me to see what to expect.
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I like the graphical one too, but for flight planning (meaning picking a number to put in your calculations for a specific flight leg), what do folks use if not the Wind Aloft product from DUATS or FSS?
 
We use Skew-T for thermal prediction, strength and top of usable lift.
Can be used to computer "trigger temperature", when the thermals will start as the day warms up.

And yes, winds aloft, shear bouncy and other predictors.
 
BillTIZ said:
We use Skew-T for thermal prediction, strength and top of usable lift.
Can be used to computer "trigger temperature", when the thermals will start as the day warms up.

And yes, winds aloft, shear bouncy and other predictors.
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You must be a glider! Right?
 
Tracey said:
Thanks. Checking multiple sites of Skew-T's could be very valuable... you can probably get a good sense of how wx is progressing. Where do you get the graphical winds aloft info?
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http://aviationweather.gov/adds/winds/

TMetzinger said:
I like the graphical one too, but for flight planning (meaning picking a number to put in your calculations for a specific flight leg), what do folks use if not the Wind Aloft product from DUATS or FSS?
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Well, if you use fltplan.com, it will calculate your winds automatically. Since that's what I use typically, it makes it easy. :)

You're correct that, for traditional flight planning, the text-based winds aloft forecast is the way to go.

BillTIZ said:
We use Skew-T for thermal prediction, strength and top of usable lift.
Can be used to computer "trigger temperature", when the thermals will start as the day warms up.

And yes, winds aloft, shear bouncy and other predictors.
Click to expand...

Now, those glider-ish things are bits I don't know how to extract out of the Skew-T, but that would be nifty to learn! :)
 
As far as I know, from DUATS/FSS.

It just makes it easier on the people filing.
 
TMetzinger said:
I like the graphical one too, but for flight planning (meaning picking a number to put in your calculations for a specific flight leg), what do folks use if not the Wind Aloft product from DUATS or FSS?
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Tim, go to Scott Dennstaedt's web site www.avwxworkshops.com and scroll down to his article about what is wrong with the Winds and Temperatures Aloft (FB) forecast. My personal opinion is that it is good only for the purpose of answering test questions because too many stars have to align in order for the FB to be even close to accurate.

Bob Gardner
 
bobmrg said:
Tim, go to Scott Dennstaedt's web site www.avwxworkshops.com and scroll down to his article about what is wrong with the Winds and Temperatures Aloft (FB) forecast. My personal opinion is that it is good only for the purpose of answering test questions because too many stars have to align in order for the FB to be even close to accurate.

Bob Gardner
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Got it. So what are we supposed to use in real life instead? That's the question that hasn't been answered (to my satisfaction at least) yet.
 
Tracey, it is the balloon runs (RAOBS) that occur twice a day. When you go to http://rucsoundings.noaa.gov to look at a Skew-T, the "ruc" stands for "rapid update cycle." The weather geeks certainly take the result of the RAOB into account when producing the Skew-T but they also apply data from dozens of other sources.

Bob Gardner
 
Tracey: the NWS has required its forecasters to specify temperatue, dewpoint and winds (predictively) at EVERY altitude for about 10 years. It has been verified enough to be an "in service" product now for about 2 years.

Each "alpha lettered" airport has that rapid update cycle forecast for 3 hours ahead. That's why it's of value.
 
bbchien said:
Tracey: the NWS has required its forecasters to specify temperatue, dewpoint and winds (predictively) at EVERY altitude for about 10 years. It has been verified enough to be an "in service" product now for about 2 years.

Each "alpha lettered" airport has that rapid update cycle forecast for 3 hours ahead. That's why it's of value.
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OK, aside from the Skew-Ts, is there a way to get this data in any sort of automated fashion so it could be imported?

Or are the only two options:
Look up the Skew-Ts and grab the wind data forecast for the airports nearest your route, manually, and plug them into your flight calculations.
or
Use an automated tool (AOPA, fltplan.com, Jepp Flight Star, FF, Dest Direct, etc.) which probably plugs in winds from the FB product in a DUAT download.

I love the idea of better wind aloft information, but the impression I have so far is that it's not integrated into any automated tools, or published as part of a standard briefing in a way that helps with flight planning.
 
Tim, if you automated it (you can get the data in ascii format) you would not get the "big" picture, e.g, where the warm middle shelf is, where the tops are, what the moisture content is of the layer below 0 deg. C, etc.

This is correlative, a level above previous flight planning tools- and it IS understandable by all, after you work it for a while.

The value is principally:

Where are the tops, and the layers.
Where is there going to be ice.
How moisture laden is that layer- light rime or clear or somewhere in between?
Do I climb or do i descend?
Understanding unstable air along the route. As in, "I believe we're going to have either thundersnow or a thunderstorm tomorrow...."
 
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Bruce,

What I'm looking for is better wind data. So far I've heard the current product is poor but no better solution is given. I understand all the OTHER good stuff a skew-t provides, but right now I want to know what a good pilot is supposed to use for wind data.

Sent from my ADR6300 using Tapatalk
 
TMetzinger said:
Bruce,

What I'm looking for is better wind data. So far I've heard the current product is poor but no better solution is given. I understand all the OTHER good stuff a skew-t provides, but right now I want to know what a good pilot is supposed to use for wind data.

Sent from my ADR6300 using Tapatalk
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A skew t provides by far more accurate wind data. The RUC2 model updates hourly. Keep in mind that skew-t is still a model using data from multiple sources it's not the raw output of the weather balloons which is why it provides pretty accurate data at any three lettered airport. The model seems to work quite well.

The difference is that the nearest winds aloft forecast for me is often 50 miles away and can only show me winds at 3000 ft intervals. It's essentially worthless, a lot can change in weather in 50 miles. It also updates way too slow so if there is a front coming through it'll be crap.

I've found the skew-t data to be surprisingly accurate and use it all the time in sky diver operations. It very closely matches the real world wind all the way up to as high as I go (11,500). The nearest winds aloft forecast to the drop zone is 34 miles. It's very often quite different and I've yet to see a time where the skew-t doesn't beat it out in accuracy.

So, YES, the skew-t is still a better source of wind if that's all your interested in. But it also offers a lot more.

As to what you're "supposed to use"? I guess I don't understand what you're getting at. It's not an aviation product but one isn't required to use an aviation product to analyze winds. Use all the tools available, the meteorologists like Scott say it's way better then the winds aloft product so I tend to believe them.
 
Wow, thanks everyone, this is excellent info. And the website that Bob listed, thanks for that too. Bob, I didn't realize that they took data from other sources as well, that would make it seem more reliable, I would imagine, but you still think that it's only good info for test questions? Or did I misunderstand you? Jesse and Bruce- thanks-- it sounds like the Skew-T is a pretty reliable source for what is going on up there.
 
Tracey the gist is that the textual winds aloft that are usually used for PP flight planning practice with the E6B are not very reliable and so Bob said that they are mostly useful for taking tests and filling out your navlog with the understanding that as you begin your cross country flight you will discover that the wind isn't like you expected and so you make adjustments enroute. However, the skew T is a better predictor of actual circumstances and will be easier to know what to expect on a flight.
 
So, is the consensus that we should teach our students that after they complete their checkrides, they should get the wind data they plug into their flight plan forms or spreadsheets or whatever, from the Skew-T data for the nearest reporting point at their planned altitude and for the appropriate time?

That makes sense to me, don't get me wrong, I just want to be sure that the Skew-T is the "better" wind data we should be using (and teaching).
 
That's certainly how it seems to me, however, why can't they just use the better wind info during training? Surely if there is a proper reasoning behind making that choice then the choice would be acceptable?
 
Tracey said:
You must be a glider! Right?
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Or a glider, soaring pilot, yes.
Along with a few other flying devices.

It's easy enough to learn to read a skewT, but easier shown, then typed here.
There are great books on it, Gliem aviation weather is one. A whole chapter on soaring forecasts ans skewT.
 
Jeanie said:
Tracey the gist is that the textual winds aloft that are usually used for PP flight planning practice with the E6B are not very reliable and so Bob said that they are mostly useful for taking tests and filling out your navlog with the understanding that as you begin your cross country flight you will discover that the wind isn't like you expected and so you make adjustments enroute. However, the skew T is a better predictor of actual circumstances and will be easier to know what to expect on a flight.
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Thanks Jeanie...this sums it up well, this is what I was looking for, thank you.
 
TMetzinger said:
So, is the consensus that we should teach our students that after they complete their checkrides, they should get the wind data they plug into their flight plan forms or spreadsheets or whatever, from the Skew-T data for the nearest reporting point at their planned altitude and for the appropriate time?

That makes sense to me, don't get me wrong, I just want to be sure that the Skew-T is the "better" wind data we should be using (and teaching).
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We should teach our students to use all the resources available to them including the limitations of the various resources. They need to learn to use some common sense - not use X product because that is the only thing on Y written.
 
TMetzinger said:
Got it. So what are we supposed to use in real life instead? That's the question that hasn't been answered (to my satisfaction at least) yet.
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My answer is: Skew-T. More reporting points, no interpolation, lots of goodies that the FB does not supply.

Bob
 
bobmrg said:
My answer is: Skew-T. More reporting points, no interpolation, lots of goodies that the FB does not supply.

Bob
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Thanks! That's what I THOUGHT the message was, I wanted to be sure I was getting it properly.

Now if it could just be part of the standard briefing I get...
 
bobmrg said:
My answer is: Skew-T. More reporting points, no interpolation, lots of goodies that the FB does not supply.

Bob
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They stopped weekend balloon launches years ago at KDRA, Desert Rock NV. That really screwed us for weekend cross country soaring forecasts. Then the stopped it all together.

Now I rely on virtual skewT that can be found on the Internet. Plus services like Dr Jack's Blipmap and XC-Soar for thermal forecasts.
 
Tracey, read the Wikipedia discussion of the Rapid Update Cycle. It says plots are available once per hour to conform with the data coming in from METARS.

In late February, NOAA is going to something called the RAP; I'm trying to learn more about it.

Bob Gardner
 
bobmrg said:
Tracey, read the Wikipedia discussion of the Rapid Update Cycle. It says plots are available once per hour to conform with the data coming in from METARS.

In late February, NOAA is going to something called the RAP; I'm trying to learn more about it.

Bob Gardner
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Bob, thank you, I will. And interesting, once an hour, huh? Makes them pretty dang reliable. :yesnod:

You'll have to teach us what the RAP is... besides terrible music.:)
 
scottd said:
First, a Skew-T log (p) diagram is a thermodynamic chart. It has nothing to do with rawinsondes (weather balloons) that get launched routinely twice a day. The data from the rawinsonde flight is called a rawinsonde observation or RAOB. RAOB data can be plotted on a thermodynamic chart such as the Skew-T log (p) diagram, Stuve diagram or Tephigram (all are thermodynamic charts).

Also, pressure, temperature, dewpoint and wind data from forecast models such as the Rapid Update Cycle (RUC), North American Mesoscale (NAM) or Global Forecast System (GFS) can also be plotted on the same thermodynamic charts.

The advantage of using the RUC model data is that its temporal and spatial resolution are much better than you can get with the FBWinds. If you want to use low resolution data from a DUATS or FSS briefing, that's fine. Just understand that there are some gotchas as I discuss in this free workshop.

I hope this helps.
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Scott, this is really helpful- thank you so much! I appreciate you taking the time to explain this, thank you.
 
Tracey said:
Scott, this is really helpful- thank you so much! I appreciate you taking the time to explain this, thank you.
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Scott explains it best. He is a great asset to general aviation.
 
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