confusing METAR sky conditions

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Just saw this METAR:

KBNW 202035Z AUTO 30010KT 10SM SCT034 BKN050 SCT065 21/15 A2983 RMK AO2

I'm confused that a scattered layer can be reported at 6500 when there is a broken layer at a lower altitude. I was under the impression that you could never have a layer at a higher altitude reported with a lower coverage than one at lower altitude. Am I mistaken or is this report erroneous?

 

[denverpilot]

They knew the chemtrail aircraft was overhead. Shhhh.

 

[Let'sgoflying!]

Nate has it. But to put it out publicly like that. We are going to need a code word for CTs.

 

[Sundancer]

Confession - I quit looking at/interpreting those 1950ish glyphs a decade or so back. I mean, I remember some of it; let's see:

the 20th day of the month, automated reporting winds 300 @ 10, 10 miles vis, scattered at 3,400, broken at 5,000 and scattered at 6,500, temp 21, dew point 15(assume C), altimeter 29.83. I guess RMK means remarks, and don't know the AO2.

Please don' tell me what I got wrong. Or right. Cause I'd never use that format to check the weather for a real flight anyway. . .

 

[denverpilot]

A02 means the system is automated, but doesn't mean it wasn't manned by a human, and that it has a precipitation sensor.

AUTO indicates that it wasn't taken by a human.

A01 means no precip sensor.

And I don't think any of the translators out there ever bother to tell you the A01/A02 information, which can actually be useful when you notice that it should be precipitating at that station, and yet there is no mention of rain begin or end times for that station.

Hmmm, oh it's A01. The airport was too cheap to buy the sensor.

 

[Lindberg]

Just saw this METAR:

KBNW 202035Z AUTO 30010KT 10SM SCT034 BKN050 SCT065 21/15 A2983 RMK AO2

I'm confused that a scattered layer can be reported at 6500 when there is a broken layer at a lower altitude. I was under the impression that you could never have a layer at a higher altitude reported with a lower coverage than one at lower altitude. Am I mistaken or is this report erroneous?

According to the NOAA, it's erroneous:

When multiple layers are visible, the Sky Cover for any given layer is the total of the sky hidden by any surface-based layer plus the amount of sky covered by all layers aloft that are below the layer being evaluated plus the layer being evaluated.

. . .

Always start evaluating sky cover at the lowest layer. As you evaluate the sky cover of each layer above, the amount determined must be either equal to or more than the previously evaluated lower layer.
​

More here: http://www.srh.noaa.gov/srh/dad/sfc/chapter5.pdf

As others have said, this is an automated observation. I don't think you'd ever see such a report from a human observer. And frankly, I have no idea how the automated ceilometer could come up with that.

 

[denverpilot]

As others have said, this is an automated observation. I don't think you'd ever see such a report from a human observer. And frankly, I have no idea how the automated ceilometer could come up with that.

Time delay of measurements before timing out. It integrates what it thinks are cloud layers over time and creates a best guess at coverage from a device that's only able to see straight up.

And that one is doing it wrong.

 

[Joshuajayg]

Time delay of measurements before timing out. It integrates what it thinks are cloud layers over time and creates a best guess at coverage from a device that's only able to see straight up.

And that one is doing it wrong.

My guess was the timing allowed the higher scattered layer to remain in the broadcast as the broken layer moved in below it. So in maybe five minutes, the higher scattered layer would disappear from the METAR.

Best guess, not based on real facts.

 

[denverpilot]

My guess was the timing allowed the higher scattered layer to remain in the broadcast as the broken layer moved in below it. So in maybe five minutes, the higher scattered layer would disappear from the METAR.

Best guess, not based on real facts.

That's my guess also, but there is a spec for how those sensors are supposed to work when that happens and I haven't bothered to go find it and read it again to see if it's normal or not.

When I joked that it's "doing it wrong" that was compared to a human-collected weather observation.

 

[Joshuajayg]

That's my guess also, but there is a spec for how those sensors are supposed to work when that happens and I haven't bothered to go find it and read it again to see if it's normal or not.

When I joked that it's "doing it wrong" that was compared to a human-collected weather observation.

Plus you are a computer guy. You are allowed to talk about programs like they are humans.

 

[denverpilot]

Plus you are a computer guy. You are allowed to talk about programs like they are humans.

I try to tone down the "some idiot wrote this code" but it leaks through. Haha. Computers just do exactly what us stupid humans tell them to do, over and over, with precision. Ha.

Basically a view into the screwed up human brain.

Made a career out of figuring out what stupid assumptions or actions other humans made with their computers.

What's interesting after doing that for 20 years is how predictable and repetitive the same sorts of mistakes are.

Missing how real humans do something when translating it into code is by far the most common error coders make. It's rare they go learn how to do Task X themselves or ask an expert before they start coding.

Deja Fu: The feeling you've been kicked in the head like this before...