About 100 flights were cancelled at Stansted on Sunday as bank holiday thunderstorms wreaked travel chaos.
Disruption continued into bank holiday Monday with Ryanair and Jet2 among airlines forced into cancellations and delays.
Jet2 passengers on flights from Larnaca and Rhodes both reportedly suffered 19-hour delays returning to Stansted, with Fuerteventura and Paphos flights 17 hours behind schedule.
Thomas Cook Airlines flights from Antalya and Dalaman in Turkey were around 20 hours late arriving at Stansted.
It follows a weekend when Thomas Cook passengers flying from Gatwick to Dalaman in Turkey, Hurghada in Egypt and Bourgas in Bulgaria experienced delays of around 24 hours, The Independent reported.
Stansted said on Sunday: “Due to an earlier lightning strike, the aircraft fuelling system was unavailable for a period this morning.
“Engineers have been on site and have now restored the system, however flights may still be subject to diversion, delay or cancellation.
“We apologise for the inconvenience and advise all passengers to check with their airlines for their latest flight updates.”
Airlines face further disruption this week with a planned walk out by Greek air traffic controllers between 10am and 1pm local time tomorrow (Wednesday).
Controllers in Italy also plan a “day of action” between 1pm and 5pm local time on June 8.