Gatwick says it can handle 11 million more passengers a year by 2030 without needing a second runway.
The airport's publishing plans for its future later today.
Gatwick currently handles around 34 million passengers a year but says it could handle up to 45 million. One of their aims is to get more people to travel to the Sussex terminals by train.
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Cloudy and breezy for much of the day. Rain and stronger winds arriving tonight.
A mostly dry but cloudy morning. Heavy rain and stronger winds this evening.
Another cloudy and breezy day tomorrow. Turning windy with rain arriving tomorrow evening.