Just for the fun of it, I turned the News and Interests feature on so I'd see the weather widget this morning. It is updating itself as the morning has gone on. I do NOT have the Reduce Taskbar updates or Open on hover options checked.
The update interval seems to be at least 30 minutes, possibly a bit more, between checks. It went from a fog alert (which we did have) and 48 degrees F to cloudy and 52 degrees and, just now, to partly sunny and 55 degrees. My mouse pointer is nowhere near to the taskbar so it's not because of anything I'm doing that it's updating.