What is a surface analysis chart?

• A. A map of terrain elevations and obstacles.
• B. A chart showing upper atmosphere wind speeds aloft.
• C. A report that depicts an analysis of the current surface weather. Shows the areas of high and low pressure, fronts, temperatures, dewpoints, wind directions and speeds, local weather, and visual obstructions.
• D. A device for measuring surface humidity.

Answer: (C)

A surface analysis chart is a summary of the weather conditions at ground level. It combines observations to show where high and low pressure systems are, where fronts lie, and the temperature and dewpoint at various locations. It also includes wind directions and speeds, observed local weather, and any visual obstructions affecting visibility. This single chart helps pilots assess what the weather will be like at airports and along a route, especially things like fog, precipitation, haze, or low visibility that can impact takeoffs, landings, and flight planning. It’s different from winds aloft charts, which depict upper-atmosphere winds, and from topographic maps or humidity instruments, which serve other purposes.