We had a great hike in the rain. The road had a few deep puddles - at the time it would have been challenging (but not impossible) for a lower clearance car to get to the trailhead. The hike itself was not very crowded, we probably saw about 6 other parties. Another reason we picked this trail is because it is divided into a lower and upper trail - which was helpful for reducing trail density for social distancing.
I'd recommend starting with the lower trail - it's both shorter and it is along the river. We took the longer upper trail on the way back - we liked the upper trail as well (quieter and easier on our tired legs), we're glad we did both.
Both trails had some portions where they were muddy and/or were mainly puddles, and there were some stream crossings. Nothing impossible, but be prepared for wet feet if you don't wear the right shoes. There are also some downed trees that require a bit of scrambling over or under.
As the hike description says, a bit after the trails rejoin, you have the option of walking straight and climbing over some fallen trees to the river for a nice viewpoint. But there's no trail up the hill from here - so afterwards, go back to where you left the trail to start the switchbacks up (it should be marked by a rock with some paint on it).
On the drive back (about 5 miles from the trailhead) we saw a black bear!