The natives are restless

Both of my cats are indoor-only, and usually don't seem to be bothered
by rain. However, today for some reason, they are very restless.

They've gotten into the habit of spending most of the day on my bed,
with Koala usually under the quilt on top. They may come out to ask for
treats when I'm fixing my lunch, but usually they go back to the bed by
the time I sit down to eat.

I eat my meals in my recliner. Today they were both in the living room
while I ate my lunch. Pickles jumped up in my lap as I started to eat,
and I encouraged her to get down, since I don't allow cats on my lap
while I'm eating. I had barely finished when Koala jumped up. He walked
around on my lap, checked out the small tables on each side of my chair,
then jumped down. About a minute later he repeated the process. He did
this several times, once lying down, but getting up almost immediately.
A little later Pickles came up and settled on my lap for several minutes.

I wonder what's different about this rain to make them so restless.
There's no thunder an lightning.