Definition
A concise weather forecast issued for the area within a five statute mile radius of an airport, covering expected surface wind, visibility, weather phenomena, and cloud conditions for a defined period (typically 24 or 30 hours). TAFs are issued routinely four times per day and are amended when conditions change significantly.
Plain English
A short weather forecast for a specific airport, telling pilots what wind, visibility, and clouds to expect there over the next day or so.
Context Anchor
Seen in preflight weather planning, especially when deciding whether departure, destination, or alternate airport weather is suitable.
Derivation
Terminal here means the airport end-point of a flight, not 'final.' Aerodrome is an older British/international word for an airport, from the Greek aer- ('air') and dromos ('running track' or 'course') -- literally an 'air course.' So a Terminal Aerodrome Forecast is a forecast made specifically for an airport.
Why Pilots Care
Pilots use it to decide whether weather at the destination will allow a safe landing or whether an alternate airport must be planned.
Intuition Check
Terminal does not mean “final” or “the end” here. It means the airport area the forecast applies to.
Example Sentence 1
Before departure, the pilot reviewed the TAF for the destination and noted that visibility was forecast to drop below minimums two hours after the planned arrival.
Example Sentence 2
Because the Terminal Aerodrome Forecast showed improving visibility after noon, the flight was delayed until conditions cleared.