Definition
AMDAR is an international program in which commercial aircraft automatically collect and transmit weather data — including wind, temperature, humidity, and turbulence — from onboard sensors during flight. The data is downlinked to ground stations and fed into weather forecasting models, providing real-time observations from altitudes and locations that surface stations and weather balloons cannot reach.
Plain English
Airliners act as flying weather stations. As they fly, their instruments record what the air is doing around them, and that information is sent to weather services to improve forecasts.
Context Anchor
Seen in discussions of upper-air observations, where aircraft reports help describe weather conditions above the ground.
Derivation
The name simply spells out what it does: 'Aircraft Meteorological Data Relay' — meteorological means relating to weather, and the aircraft relays (passes along) the data. The program was developed by the World Meteorological Organization to make use of the thousands of airliners already flying through the atmosphere every day.
Why Pilots Care
Supplies frequent real-time upper air data that improves forecast accuracy for route planning and turbulence avoidance.
Grounding Statement
Picture an airliner climbing out of an airport while its onboard equipment quietly reports the temperature and wind it is actually experiencing.
Intuition Check
AMDAR is not a forecast by itself. It is a source of real weather observations that can be used to make forecasts and weather products better.
Example Sentence 1
Wind and temperature data from AMDAR-equipped airliners gives forecasters a clearer picture of the upper atmosphere between weather balloon launches.
Example Sentence 2
Forecasters incorporated AMDAR reports into the updated winds aloft forecast for the departure area.