Definition
A ground-based Doppler weather radar system installed at or near major airports to detect hazardous wind conditions in the terminal area, particularly low-altitude wind shear, microbursts, and gust fronts that threaten aircraft during takeoff, approach, and landing. TDWR provides higher resolution and more frequent updates than long-range weather radars and is optimized to scan the airspace below 1,000 feet near runways. Detected hazards are relayed to air traffic controllers and issued to pilots as wind shear and microburst alerts.
Plain English
A weather radar near an airport that watches for sudden, dangerous wind changes close to the runway and warns controllers and pilots when it sees them.
Context Anchor
Pilots usually encounter TDWR indirectly through air traffic control weather alerts, airport wind-shear alerts, and weather discussions for large terminal areas.
Derivation
Terminal refers to the airspace near an airport, where arrivals and departures occur. Doppler refers to the Doppler effect — the shift in returned radar signal frequency caused by motion toward or away from the radar — which lets the system measure wind speed and direction, not just precipitation.
Why Pilots Care
Provides early warning of low-level wind shear that can cause sudden loss of lift during takeoff and landing.
Grounding Statement
If a thunderstorm sends fast-moving air across the approach or departure path, TDWR is designed to spot that hazard near the airport.
Intuition Check
Terminal does not mean the airport passenger building here. It means the airport area where aircraft are arriving, departing, and operating close to the ground.
Example Sentence 1
Tower advised inbound traffic that TDWR was reporting a microburst alert on final for Runway 27.
Example Sentence 2
Pilots review TDWR reports during preflight weather checks at equipped airports.