I have been out of town the last few days and just returned.
I didn't have access to the webcams so I've not monitored recent conditions.
I just logged in and saw something odd on the TEPCO 4 cam.
Compare the TEPCO 4 cam screenshots below, focusing on what looks like a column of steam or smoke emerging from the below the cam view in the vicinity of reactor 3 in the first screenshot.
The column was mostly gone a few minutes later but you can still see a darker smudged area where the column appeared to have emerged from:
A trick of the light or emissions?
Here is a pdf of more screenshots: