And I've now added the predicted cancellations for tomorrow in the Wiki.
- 170/652 departures and 182/578 arrivals cancelled at Heathrow
- 20/337 departures and 26/254 arrivals cancelled at Gatwick
- 19/129 departures and 24/135 arrivals cancelled at London City
Again, the numbers and detail will be subject to small errors as my method to grab data from flightradar24.com is not foolproof.
Come to think about it, I'm not foolproof either.