Question for met experts

[Strawb (Dave)]

Why when the cloud cover is 50% does the cloud ALWAYS remain whenever one wants to look?? So fustrating of late up here.

[Atmos (Colin)]

According to QED and taking a probability waveform into consideration while also not forgetting Pauli or Schrodinger; there is a 50% chance that the clouds exist but a 100% chance that they exist while being observed. Get the idea

[AstralTraveller (David)]

I'm sorry but the interplay between astronomers and clouds is not a question of science. Such questions should be addressed to mystics, druids and shamen - bring your own goat.

[julianh72 (Julian)]

It's the same underlying law of the universe that guarantees:

. The toast always falls butter-side down
. When trying to plug a USB cord into a computer, it always takes two goes to get it the right-way up
. Any article or statement about correct grammar, punctuation, or spelling is bound to contain at least one eror.

Conversely, whenever an action hero such as McGyver needs a 1000:1 long-shot to achieve their aims (saving the girl, or saving the world), it always comes off.

[julianh72 (Julian)]

Originally Posted by Atmos

According to QED and taking a probability waveform into consideration while also not forgetting Pauli or Schrodinger; there is a 50% chance that the clouds exist but a 100% chance that they exist while being observed. Get the idea

I prefer the "many worlds" interpretation:

Somewhere out in the multiverse, there exists a world where I take my telescope outside, and the clouds DON'T immediately roll in.

I know it sounds implausible, but according to quantum dynamics, it's actually true - I just wish it was the world that I live in!

[multiweb (Marc)]

Originally Posted by Strawb

Why when the cloud cover is 50% does the cloud ALWAYS remain whenever one wants to look?? So fustrating of late up here.

When it says 50% I like to think it's 50/50 clouds and sucker holes. 50% solid translucent soup is too depressing to think about.

[Wavytone]

Originally Posted by Strawb

Why when the cloud cover is 50% does the cloud ALWAYS remain whenever one wants to look?

'Cause the BOM definition of "clear" is "not raining". And they don't even look out the window. Being low ranking public servants it's quite possible they don't have a window to look out of.

And the other websites make it up most of the time on the basis that if tomorrow's forecast is same as yesterday they'll be right 90% of the time anyway.

[sil (Steve)]

"every action has an equal and opposite reaction", remember.

Therefore the photon energy hitting your telescope is reflected back up through the atmosphere, energising nucleation to begin cloud formation.

Its the same science when washing a car. The newly polished surfaces reflect the sun's energy back up to kickstart cloud formation. Can I have a Phd now please? or at least some grant money so I can buy a range of telescopes and shiny sports cars to determine the effect of surface area on cloud size and formation rate.

[Camelopardalis (Dunk)]

Originally Posted by Wavytone

'Cause the BOM definition of "clear" is "not raining". And they don't even look out the window. Being low ranking public servants it's quite possible they don't have a window to look out of.

And the other websites make it up most of the time on the basis that if tomorrow's forecast is same as yesterday they'll be right 90% of the time anyway.

The models they produce do have a value for cloud cover but it just doesn't feature on their website. Clients that consume the data can and do use the cloud data - for example, CFN.

The BOM office has lots of windows, it's just in Melbourne so there's little point in looking out most of the time