I went out this afternoon and found yellow jackets going in and out of hive (I had the reducer on with the wider entrance in use -- just turned to smaller entrance). I haven't been out for about 5 weeks, figuring they were ok -- we've had a warm snap (record 74 degrees yesterday -- hottest Nov. day ever recorded here). But the hive was quiet. I smashed about 20 yellow jackets, saw 2 or 3 honey bees.
Now what? It's supposed to freeze tonight -- can I cover with a sheet for 24 hrs?
Also -- bad sign? -- I didn't hear any humming from the hive. I didn't dare open it up with the yellow jackets all over, but they seem to be coming and going at leisure. I duct taped the small ventilation hole above the main entrance, which I had forgotten was there, the one on back was already taped. I have an upper entrance in my inner cover, but left it open for air.