Sleeping Yellow-Faced Bumble Bees

How sweet.
Yesterday morning I discovered these two Yellow-faced bumble bees Bombus vosnesenskii asleep on separate nude buckwheat Eriogonum nudum flower heads.
It was cloudy with fog most of the day, with a cold, relentless wind.
The flower heads swayed back and forth in the wind, with both bees hanging on.

Here is the same bumble bee from another angle.
If you look carefully you can see light flecks of pollen on the bee.

The other bumble bee was asleep, curled over the top of another flower head of the same plant.

And here is an overhead shot of bumble bee number two.