Amazing Kelvin-Helmholtz clouds, but what's below them?

[Ann]

A Swedish tabloid posted this picture today:

Kelvin-Helmholtz clouds. Photo: Rachel Gordon

---

These are Kelvin-Helmholtz clouds. You can read about them here.

Okay, but here's my question. What's below these clouds?

There appears to be a mountain range below them. Yes, but below that mountain range there appears to be white clouds, and below them blue sky, and below the blue sky more mountains and a horizon.

Is that top mountain range a mirage? Or are the white clouds and blue sky below the top mountain range a mirage? Or is that "blue sky" really a lake, and the seeming white clouds really white foam as waves are crashing onto rocks?

What are we seeing in this image?

The picture was taken in Wyoming.

Ann

[Chris Peterson]

A Swedish tabloid posted this picture today:

Kelvin-Helmholtz clouds. Photo: Rachel Gordon

---

These are Kelvin-Helmholtz clouds. You can read about them here.

Okay, but here's my question. What's below these clouds?

There appears to be a mountain range below them. Yes, but below that mountain range there appears to be white clouds, and below them blue sky, and below the blue sky more mountains and a horizon.

Is that top mountain range a mirage? Or are the white clouds and blue sky below the top mountain range a mirage? Or is that "blue sky" really a lake, and the seeming white clouds really white foam as waves are crashing onto rocks?

What are we seeing in this image?

The picture was taken in Wyoming.

Ann

I see stuff like this all the time from my deck (well, the Kelvin-Helmholtz clouds are usually less impressive, but otherwise similar). Below the high cirrus clouds we see the K-H clouds, below that the mountains, and below that we see a layer of fog with the top burning off. And below that the nearby foothills or piedmont.

[Ann]

A Swedish tabloid posted this picture today:

Kelvin-Helmholtz clouds. Photo: Rachel Gordon

---

These are Kelvin-Helmholtz clouds. You can read about them here.

Okay, but here's my question. What's below these clouds?

There appears to be a mountain range below them. Yes, but below that mountain range there appears to be white clouds, and below them blue sky, and below the blue sky more mountains and a horizon.

Is that top mountain range a mirage? Or are the white clouds and blue sky below the top mountain range a mirage? Or is that "blue sky" really a lake, and the seeming white clouds really white foam as waves are crashing onto rocks?

What are we seeing in this image?

The picture was taken in Wyoming.

Ann

I see stuff like this all the time from my deck (well, the Kelvin-Helmholtz clouds are usually less impressive, but otherwise similar). Below the high cirrus clouds we see the K-H clouds, below that the mountains, and below that we see a layer of fog with the top burning off. And below that the nearby foothills or piedmont.

Thanks, Chris. So what looked like blue sky to me was actually fog, and what looked like white clouds was the fog burning off.

Ann

[Chris Peterson]

A Swedish tabloid posted this picture today:

Kelvin-Helmholtz clouds. Photo: Rachel Gordon

---

These are Kelvin-Helmholtz clouds. You can read about them here.

Okay, but here's my question. What's below these clouds?

There appears to be a mountain range below them. Yes, but below that mountain range there appears to be white clouds, and below them blue sky, and below the blue sky more mountains and a horizon.

Is that top mountain range a mirage? Or are the white clouds and blue sky below the top mountain range a mirage? Or is that "blue sky" really a lake, and the seeming white clouds really white foam as waves are crashing onto rocks?

What are we seeing in this image?

The picture was taken in Wyoming.

Ann

I see stuff like this all the time from my deck (well, the Kelvin-Helmholtz clouds are usually less impressive, but otherwise similar). Below the high cirrus clouds we see the K-H clouds, below that the mountains, and below that we see a layer of fog with the top burning off. And below that the nearby foothills or piedmont.

Thanks, Chris. So what looked like blue sky to me was actually fog, and what looked like white clouds was the fog burning off.

Ann

That's how I see it. Indeed, "fog" may not be the right word. I think that air is saturated with water vapor, right on the edge of being fog (and there's probably a little bit of actual fog in there). The blueness is likely a consequence of scatter within that zone (fog is large particles that scatter white, but water vapor scatters blue) as well as additional scatter along the path between there and the camera.