Does the FAA define Fog as a Cloud?

[NealRomeoGolf]

The PHAK already answers my question, by the way. Chapter 12 page 12-15 states "Fog is a cloud that is on the surface."

So yesterday's little fog phenomenon on the runway (and nowhere else) means that even in Class G airspace, you cannot takeoff in something as benign as this since you wouldn't be "clear of clouds."



It was gone by the time I started the engine.

 

[Rgbeard]

I would define this as an area of restricted visibility.

 

[NealRomeoGolf]

It would have been interesting to taxi into to see what the vis was. From the side, it looked like the cockpit would have been above the fog. It was an interesting thought provoking thing to ponder. It was only over the runway and nowhere else.

 

[NealRomeoGolf]

By the way, I took off from the clear end (in those pictures) of the runway and would have rotated before the fog. So then clear of clouds and not illegal (nevermind the not smart argument)?

Like I said....it was gone before I could venture more thought about it. Maybe I think about this stuff more since I am studying for my instrument written.

 

[Larry in TN]

That is Shallow Fog, MIFG.

 

[flyingron]

"Mist"

 

[Larry in TN]

"Mist"

Mist is "thin" fog. The dividing line is 1km or 5/8mi.

Anything up to 5/8mi is FG. Greater than 5/8mi is BR.

 

[Shawn]

FAA's defintion of a cloud...

13.1 Introduction. A cloud is a visible aggregate of minute water droplets and/or ice particles in the atmosphere above the Earth’s surface. Fog differs from cloud only in that the base of fog is at the Earth’s surface while clouds are above the surface

https://www.faa.gov/documentlibrary/media/advisory_circular/ac_00-6b.pdf

 

[NealRomeoGolf]

Mist is "thin" fog. The dividing line is 1km or 5/8mi.

Anything up to 5/8mi is FG. Greater than 5/8mi is BR.

So that layer was probably about 2600 feet.....so about half a mile. The runway in total is 4001 feet and it did not go the whole length. So I guess it was fog.

 

[Larry in TN]

So that layer was probably about 2600 feet.....so about half a mile. The runway in total is 4001 feet and it did not go the whole length. So I guess it was fog.

As I said above, what I see in the pictures is Shallow Fog. The METAR code is MIFG.