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mattwht

Predicting cloud coverage

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Hey guys,

So I'm trying to schedule a day where I can possibly do multiple AFF jumps in one day, but I'm worried about weather, specifically clouds, making the day worthless.

Does anyone know of how to predict cloud coverage? I've looked at weather sites, but all I really see is the same general "partly cloudy", "overcast", etc type of predictions.

Is there some sort of almanac, or is it just sort of luck?

Also, my DZ is about an hour away, so that factors in to it as well, cause while the sun may be shining where I am, it could be poor weather there (which has happened twice to me now).

Thanks in advance!

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I live an hour and a half from my DZ. If I step outside at my house and its complete cover, I check the automatic report METAR data that reports near my DZ. If it looks sketchy, I just call and see what they say it looks like down there. Saved me a few trips that would've ended in no jumps. Although if you are already in AFF and are serious about getting an A license I would say if you go down there and they aren't jumping, it is the perfect time to work on things such as packing, calculating opening point, going over patterns, getting any questions you have answered, etc. On the days that no one is jumping, everyone is available with no distractions, so it is a good time to learn as much as you can without jumping. Good luck!;)

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Don't even try predict. Go to the DZ, you will learn a lot while on the ground waiting for some blue skies.
You have the right to your opinion, and I have the right to tell you how Fu***** stupid it is.
Davelepka - "This isn't an x-box, or a Chevy truck forum"
Whatever you do, don't listen to ChrisD.

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potatoman

Don't even try predict. Go to the DZ, you will learn a lot while on the ground waiting for some blue skies.



This is the right answer... Heck, i've spent more days at dz waiting for weather than jumping but those days spent waiting definitely werent wasted...

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Yes, finding aviation weather observations (METARs) and forecasts (TAFs) is the way to go. Cloud heights are also a big part of it. Non aviation general forecasts don't distinguish between 100% cloud at 1000' versus 100% at 15000'.

The forecast may unfortunately be for some larger airport nowhere close to where the DZ is, and forecasts can't be perfectly accurate. A particular layer of broken cloud won't necessarily be at all locations in a 100 mile wide area for the entire afternoon, and might dissipate in spots or completely fill in at others.

While hanging out at the DZ has its benefits, and one can't jump if one isn't at the DZ, some fore-knowledge of the weather is useful in planning one's visits.

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To get the latest information (so good for that "go/no go" decision) here's a site that lets you get METAR data reported for any Airport that has it:

http://aviationweather.gov/adds/metars/
Note 1: chose the "translated" rather than "raw" option
Note 2: to get data from an airport, you need to know its 4-letter ICAO designation. US airports generally begin with 'K' and then usually followed by the 3-letter code you often see associated with it (i.e, for Atlanta's airport, the normal 3 letter code is ATL, it's ICAO designation is KATL).

But here's a wikipedia web page that list the ICAO codes:
http://en.wikipedia.org/wiki/List_of_airports_by_ICAO_code:_K

If the place you jump at doesn't have METAR data, find ones close to them, and best to rely on the ones upwind of the generally prevailing direction weather is moving that day (usually from the west).

I don't know of any good sites for forecast data. Perhaps someone else can provide a link to something that has that.

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No! You go to dropzone!

Waiting around for 6 hours and not getting a jump in is all part of growing up! Don't forget to have a beer with the instructors and other skydivers. And help to put the planes away.

Remember, a bad day at the dropzone, even one where you didn't actually get to jump, is still better than a good day at work.
I'm trying to teach myself how to set things on fire with my mind. Hey... is it hot in here?

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Don't even try predict. Go to the DZ, you will learn a lot while on the ground waiting for some blue skies.

This is the right answer...

... to a different question than the OP asked.



Not really. The OP is asking about learning to skydive, and there's more to that than just making jumps. Even if you leave out the idea of just 'hanging around' and learning through stories and general contact with other jumpers, the A license proficiency card has a host of ground-based items that need to be completed.

The worst time to take care of those ground-based items is when the weather is good and the props are turning. When the weather is 'marginal', there will surely be some staff on hand in case it clears up, and before it does is a prime time to take care of some non-jumping business.

I'm willing to help out students and other jumpers at the DZ with any number of things time permitting. So if the loads are turning, I'm going to have very little time. If we're on a weather hold, I have nothing but time.

Add to that the learning by 'osmosis' that comes from hanging out with jumpers and taking about jumping, a trip to the DZ is a win/win when weather 'might' be a factor.

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So I just noticed pchapman used the term TAF in his post above, and recognized that as an option that I never explored at the Metar link I provided above, so I explored a bit ...

And low and behold, you can get cloud ceiling forecasts! It's in the format of the METAR data (but make sure you select "translated"!!!) but will project out for intervals into the next day.

So:
1. go to the link (http://aviationweather.gov/adds/metars/)
2. enter the ICAO code of the airport
3. select "translated"
4. Check both the METARs and the TAFs checkboxes

You'll get current conditions (METAR) and forecasted conditions (TAFs).

Quite cool!

BTW, regarding the issue of whether the answer to the question "Is there a place to find information that predicts cloud cover?" is or is not "Forget about it! Even if the weather is bad, just go to the drop zone!", I'll assume you are an adult and can manage your obligations and responsibilities yourself. I agree there is a lot of value to hanging out at the DZ as much as you can when you are new to the sport, but that many people cannot do so all the time.

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regarding the issue of whether the answer to the question "Is there a place to find information that predicts cloud cover?" is or is not "Forget about it! Even if the weather is bad, just go to the drop zone!", I'll assume you are an adult and can manage your obligations and responsibilities yourself. I agree there is a lot of value to hanging out at the DZ as much as you can when you are new to the sport, but that many people cannot do so all the time.



I get that, and beyond your A license training, there is some merit to that thought.

However, given that the OP was intending to go to the DZ to jump (aka, learn to skydive) on a given day, the type of learning should not be the controlling factor.

The A license proficiency card has in-air and ground-based items that need to be completed, and the USPA will not issue a license based on an incomplete card, regardless if the missed items are in-air, or ground-based. The USPA sees all of the items of equal importance, and so should the student. If they can make time to go to the DZ to jump on a given day, then they can also use that time to work on the ground-based learning if weather should become a factor.

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mattwht



...Does anyone know of how to predict cloud coverage? I've looked at weather sites, but all I really see is the same general "partly cloudy", "overcast", etc type of predictions.

Is there some sort of almanac, or is it just sort of luck?

Also, my DZ is about an hour away, so that factors in to it as well, cause while the sun may be shining where I am, it could be poor weather there (which has happened twice to me now).

Thanks in advance!



It's called "meteorology", the science of predicting weather.

Where are you? You might fill out your profile. Most places have reasonably predictable weather patterns.
Learning your local patterns and how to predict the weather is a reasonably straightforward process.

Depending on where you are, the easiest way to predict the weather is to know which way it usually moves and look that way to see what's happening.

I'm in Wisconsin, and most weather here moves west to east. If I want to know what the clouds are going to be like in a couple hours, I look at an overall map to see what's happening (fronts and airmasses), how it's moving (normally or not) and how fast.

There's a few other ways, like looking at the temp/dewpoint spread (in the METARS) and using that to guess cloud heights, comparing that guess to the actual reports to get an idea of the temp gradient, that sort of thing.

It's a science, not magic. Some research on the web might help, but your best bet is to talk to the pilot at the DZ...

On one of those crappy weather days when everyone is standing around. At my DZ, if the weather is iffy, someone has the satellite or radar pic up on a laptop or tablet, or is bouncing around the sites getting an idea of what's going on in the area. That's a perfect time to ask questions like:
"What are you seeing?"
"What are you looking for?"
"How is it going to move?"
"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

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The two main DZs I jump at are 1 hour 45 minutes away and 4 hours away. I am very reluctant to drive 4 hours unless it is mostly clear. I am very likely to drive 1 hour 45 minutes if it is partly cloudy. But that changes some if I jumped last weekend or if I have not jumped for 3 weekends.

As mentioned the aviation forecast shows the cloud levels, which helps. I try to use more than one source and also practice “calling it”. It is something you have to learn and it is still very much a guess and a roll of the dice.

And then there is the wind!
Instructor quote, “What's weird is that you're older than my dad!”

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mattwht

Hey guys,

So I'm trying to schedule a day where I can possibly do multiple AFF jumps in one day, but I'm worried about weather, specifically clouds, making the day worthless.

Does anyone know of how to predict cloud coverage? I've looked at weather sites, but all I really see is the same general "partly cloudy", "overcast", etc type of predictions.

Is there some sort of almanac, or is it just sort of luck?

Also, my DZ is about an hour away, so that factors in to it as well, cause while the sun may be shining where I am, it could be poor weather there (which has happened twice to me now).

Thanks in advance!



I thought you were a FL native?


Some quick thoughts....
Wait an hour,... Bring a book,...An hours drive is short,... You actually waste more time watching commercials on TV,...And or see if anyone in the state of retired pilots (FL has more retired pilots and wannabee pilots in it than any other state.) is running a Private Pilot ground school. Or get on the phone, find people at the destination, and or bug the heck out of manifest.

(Learning how to read those reports in an hour or less isn't going to happen. )

C

Good luck! :)
And here is a friendly tip when speaking to people that work and play at airports:

It's kind of insulting to hear how you are "wasting" your time waiting for the weather to change, because you have to drive only an "hour," try thinking about the pilot who has to waste his time all day, each and every day, all year long waiting there for you.... I know that's not how you meant it, so for gripes sake learn how to judge will ya and then share that with the rest of us!!!! :)
But what do I know, "I only have one tandem jump."

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Another way to check conditions is to find out if your airport has an AWOS station. The majority of them are phone-based, where you call in to get an update on the cloud cover, visibility, and winds. A few have online versions (same info presented in a graphic interface - link below). If they have one, it's a good number to have programmed into your phone. B|

It doesn't help with the forecasts, but it does help if you want to know what's going on at the moment you're making your decision to leave. Of course, it helps to have some context on the overall weather patterns. For example, I can look at a forecast at my home DZ that says 12-15 mph winds and know that it's often conservative and I probably want to check ahead of time to see if actual conditions are higher. If I wake up Saturday morning and call AWOS and the winds are already above 15, I know (from experience) that it doesn't bode well for the day since the winds will probably go up even more - our typical pattern is that the winds will go up most of the day and might drop off mid-late afternoon. If I'm only planning to go up for a day, that might convince me to stay home.

http://www.saiawos2.com/listme.php

"There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences." -P.J. O'Rourke

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You already have the correct answer. But go to the DZ with a "plan B" in case you get weathered out for a while. Take a lawn chair, a hat, and a good book to read. If you have cloud cover, enjoy your book while waiting for it to clear. Even better, hang out and chat with people.

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Divalent

So I just noticed pchapman used the term TAF in his post above, and recognized that as an option that I never explored at the Metar link I provided above, so I explored a bit ...

And low and behold, you can get cloud ceiling forecasts! It's in the format of the METAR data (but make sure you select "translated"!!!) but will project out for intervals into the next day.

So:
1. go to the link (http://aviationweather.gov/adds/metars/)
2. enter the ICAO code of the airport
3. select "translated"
4. Check both the METARs and the TAFs checkboxes

You'll get current conditions (METAR) and forecasted conditions (TAFs).

Quite cool!

BTW, regarding the issue of whether the answer to the question "Is there a place to find information that predicts cloud cover?" is or is not "Forget about it! Even if the weather is bad, just go to the drop zone!", I'll assume you are an adult and can manage your obligations and responsibilities yourself. I agree there is a lot of value to hanging out at the DZ as much as you can when you are new to the sport, but that many people cannot do so all the time.



Thanks! This is exactly the type of information I was looking for!

Yes, I know that there is a ton to learn besides actual jumping, and that weather holds is a great time to do so.

My DZ is not a seven day a week one though, and as I work in a restaurant it's already a stretch for me to get any type of weekend day off, so they are few and far between, which is why it's important to me to be able to jump each time I go. There's a huge difference to me from not being able to jump one day and heading back out in a week to try again, and not being able to go again for a month or more depending on business of the restaurant.

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mattwht

Hey guys,

So I'm trying to schedule a day where I can possibly do multiple AFF jumps in one day, but I'm worried about weather, specifically clouds, making the day worthless.

Does anyone know of how to predict cloud coverage? I've looked at weather sites, but all I really see is the same general "partly cloudy", "overcast", etc type of predictions.

Is there some sort of almanac, or is it just sort of luck?

Also, my DZ is about an hour away, so that factors in to it as well, cause while the sun may be shining where I am, it could be poor weather there (which has happened twice to me now).

Thanks in advance!



Just make friends with a weather person. Bug them for a forecast :)


I'll piggy back what others have said about the tafs/metars if the airfield you're jumping at is lucky enough to have the two. Aviation Weather Centers stuff is great, but my boss coded what all of the center weather service units use now (we're basically 23 units that work for certain chunks of airspace where as aviation weather center over sees the entire country, north pacific, and atlantic). IMO, our website is a little more user friendly: http://www.wrh.noaa.gov/zoa/mwmap2.php?map=zoa&wfo=&plot=0&limit=1

So, Oakland Centers airspace (but you can navigate to any other center's airspace in the country from this website via the drop down menu at the top). You can mouse over any of those stations (or even click on the bay area for a zoomed in bay area map) and get a pop up of the current taf, metar, sunrise, sunset, etc. If you click on it, it will open up a box with the last days observations decoded from the metar (if you want to see the raw metar, just click on the link at the top of the box). There will also be tabs up at the top that will allow you to see the latest pireps in the area (sometimes you can get pireps for cloud bases/tops), and in particular a RUC sounding. I could spend an hour trying to explain how to interpret a sounding, but if you want a quick estimate on cloud heights, usually you'll see a cloud deck where the red and blue lines on that sounding touch or almost touch. Right now that is about 20,000ft on most of the northern CA soundings, which is exactly where the cloud deck is being reported right now.

No metar to click on to see a sounding near your DZ? I hate to link you some place outside of NOAA, but this point/click user friendly sounding is great from Reed Timmers website: http://www.twisterdata.com/index.php?prog=forecast&model=GFS&grid=3&model_yyyy=2013&model_mm=12&model_dd=11&model_init_hh=02&fhour=00&parameter=TMPF&level=2&unit=M_ABOVE_GROUND&maximize=n&mode=singlemap&sounding=n&output=image&view=large&archive=false You can click anywhere on that map and get a forecast sounding.

I write the taf's for the major terminals in the bay area. It's very difficult to get cloud heights down sometimes. I definitely would not take the the local taf for gospel and think it will be like that at your dz, especially if your dz is not very close to the taf location. If you're cutting the call to go jump or not close enough to where exact cloud decks make a big difference, then I think you're over thinking it. If it's mostly cloud or overcast in the forecast, maybe don't go. If it's party cloud to sunny, then maybe head out there for the day. That probably works for most people when they're looking at jumping forecasts :)
Apologies for the spelling (and grammar).... I got a B.S, not a B.A. :)

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LyraM45


I write the taf's for the major terminals in the bay area. It's very difficult to get cloud heights down sometimes. I definitely would not take the the local taf for gospel and think it will be like that at your dz, especially if your dz is not very close to the taf location.



So YOU'RE the one!! :P

Like she said, TAFs are predictions and usually end up a tad bit off. I always hated seeing TAFs that essentially show CAVU (ceiling and visibility unlimited) only to run into some unforecast clouds popping up and messing up my days.

Now I HOPE for some IMC. :D
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
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