The bees are “bearding” by lunch time. This is a common sight on hot, humid days with a big hive and a good nectar flow. They have collected so much nectar that they cannot dry it unless some of the bees move outside and allow more ventilation space. The configuration is different from a swarming hive and it is past the swarming season. You can see from the photograph that bees are still arriving with nectar. Another test is to hold a lighted match near the opening. One side will show air going in and the other air going out. A solution might be to make larger ventilation grills in the lid or put in a spare box with grills added. I'm loath to do this because it could create a haven for SHB. I may just let them sort this out themselves rather than continually interfere.
Despite the hot humid day after baking some savoury sour-dough biscuits and weeding another garden bed I finally bit the bullet and got stuck into repairing the potholes in our 300 metre bitumen driveway. It took just over three bags of bitumen to finish the job which is just as well as that is all we had. One hole was that deep it required some filling rocks and a bit of concrete to bind it all. But the job is finished. The worst part was walking back up the steep drive to collect more bags of bitumen and when finally finished pushing the wheelbarrow with the tools home.
My list is getting shorter.