Definition
A weather product displayed on a Multi-Function Display (MFD) that shows the estimated altitude of the upper surface of cloud layers, presented graphically as a map overlay with altitude values or color shading. The data is typically derived from satellite infrared imagery and updated at regular intervals through a datalink weather service.
Plain English
A picture on the cockpit screen showing how high the tops of the clouds reach, so the pilot can see at a glance whether they can climb above them or have to go around.
Context Anchor
Seen on electronic flight displays and multi-function displays that show datalink weather in the cockpit.
Derivation
Graphical comes from graph, meaning something shown by lines, marks, or pictures. Cloud tops means the upper part of a cloud layer. Together, the term means cloud-top information shown as a picture rather than only as text.
Why Pilots Care
Allows pilots to quickly assess whether they can cruise above cloud layers or must expect turbulence, icing, or instrument conditions at their planned altitude.
Grounding Statement
If a cloud layer extends up to 9,000 feet, the graphical cloud tops display is trying to show that upper height over the area.
Intuition Check
Do not assume “cloud tops” means a perfectly flat cloud surface or guaranteed clear air at one exact altitude. It is an estimate of the upper height of cloud layers over an area.
Example Sentence 1
Before climbing through the broken layer ahead, the pilot checked the CLD TOPS page on the MFD and saw the tops reported near 9,000 feet.
Example Sentence 2
Before departure the graphical cloud tops layer showed a build-up to 18,000 feet along the route, prompting a climb to FL200.