It is weird, but at night, here in Santa Monica we have 55oF - bees from my horizontal hive - have party on the deck every night. It is not bearding - they just socialize on the deck... Bees from vertical hive - all inside after 6 p.m... The possible explanation for this is that horizontal hive has much nicer and bigger deck.
Tonight, 11oC (~52oF), 9 p.m. and midnight. Girls are out.