Air traffic control problems are causing some delays at Southend airport but not all flights are affected.
The airport says: "The advice to passengers is to keep an eye on our website, with our live departures board."
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Very warm with sunshine. Chance of thundery showers late morning.
A hot, humid and sunny start before cloud increases as a narrow band of thunderstorms spreads northeast. These clear during the afternoon.
A fine and sunny end to Friday will then be followed by a warm and muggy night. Warm and sunny on Saturday with the risk of a thunderstorm.