Nothing to do with T5 on the 31st August, the thunderstorms would have had a similar affect if it was anywhere else.
In reality my issue isn't with the lack of communication but their inability to handle what, to me, seems to be a frequent occurence of canx flights. From the BA North Lounge we were sent to Central Customer Service (gate 12-13 area) then to gate 21 then through passport control, baggage reclaim, into arrivals then back up to departures - a nice 20 min walk to arrive 100 metres from the Lounge I was in.
Yes it is 100 metres but don;t forget you are in the departures area and can't just walk back through where you came from check in. If you are 'landing' then you need to go through the proper channels back to immigration, hence the long way round to go what is a short distance in reality.
Once back in the check in area there was absolutely no system - the staff should have had plenty of notice that 1,000 pax were about to descend on them and have been organised accordingly with queues clearly marked instead of the free-for-all that occurred.
Having 1000 pax descend on anyone at short notice isn't the easiest thing to handle at the best of times.
Maybe the circumstances are exceptional but twice in 3 visits tells me it's the norm.
It is certainly not the norm, just unlucky that you happended to be flying during these events. Hope it is easier if there is a next time.