Definition
A combined weather assessment that describes two key conditions for flight: the ceiling — the height above the ground of the lowest layer of clouds reported as broken or overcast (or the vertical visibility into an obscuration) — and the visibility, which is the greatest horizontal distance at which prominent objects can be seen and identified. Together they define how much usable airspace and forward sight a pilot has, and they determine whether flight can be conducted under visual flight rules (VFR) or requires instrument flight rules (IFR).
Plain English
How low the clouds are and how far you can see. These two numbers together tell a pilot whether the weather is good enough to fly by looking outside, or whether they’ll need to fly using instruments — or stay on the ground.
Context Anchor
Used in preflight weather planning and in the PAVE checklist under Environment, especially when deciding whether the weather fits the pilot, aircraft, route, and rules for the flight.
Derivation
‘Ceiling’ comes from the Latin caelum, meaning ‘sky’ or ‘heaven,’ and was borrowed into aviation to describe the ‘roof’ of usable sky beneath the clouds. ‘Visibility’ comes from the Latin visibilis (‘able to be seen’). Pairing them captures both the vertical limit (how high you can fly before hitting cloud) and the horizontal limit (how far you can see ahead).
Why Pilots Care
These factors decide whether visual flight rules can be used and directly affect go or no-go decisions and flight safety.
Grounding Statement
Before takeoff, a pilot checks ceiling and visibility to answer a simple question: are the clouds high enough and the view clear enough for this flight?
Intuition Check
Ceiling does not mean the top of the clouds; it means the lowest significant cloud height or sky-obscuring limit above the ground. Visibility does not mean how clear the weather feels; it means how far objects can actually be seen and identified.
Example Sentence 1
The briefer reported a ceiling of 1,200 feet and visibility of 3 miles, so the pilot decided the conditions were marginal for a VFR cross-country.
Example Sentence 2
Low ceiling and visibility forced a delay until conditions allowed safe takeoff.