Definition
A research laboratory operated by the National Oceanic and Atmospheric Administration (NOAA) that developed and tested weather forecasting systems, observation tools, and data display technologies used in aviation weather services. In 2005 it was reorganized into the Earth System Research Laboratory (ESRL), and much of its aviation-related work continued under the Global Systems Division (now the Global Systems Laboratory).
Plain English
A government weather research lab that built tools and forecasting systems used to support aviation weather products. It no longer operates under this name, but the acronym still appears in older FAA materials.
Context Anchor
Seen in FAA acronym lists and older aviation weather references, especially where weather forecast systems or weather information sources are being identified.
Why Pilots Care
Pilots don't deal with FSL directly, but many of the weather tools and graphical forecast products they rely on trace back to research developed there. Recognizing the acronym helps when reading older FAA publications or background material on weather systems.
Intuition Check
Do not read FSL as a flight procedure or cockpit instruction. In this FAA context, it is the name of a NOAA weather laboratory.
Example Sentence 1
Several modern aviation weather displays grew out of prototypes developed at the NOAA Forecast Systems Laboratory (FSL).
Example Sentence 2
Weather models developed by the FSL help improve the forecasts pilots use for route planning.