The Luton airport website reports: "Owing to technical issues with Air Traffic Control, flights in or out of London Luton Airport may be affected.
"Passengers are advised to check in for their flights as normal."
More top news
Heavy showers will affect many places this morning but it will brighten up this afternoon. Feeling cooler than the last few days.
Following the hottest day of the year so far, it will be a muggy night. Showers will develop this evening and will continue tomorrow.
The Duke and Duchess of Cambridge have been in Luton today, to continue to raise awareness on mental health.