I woke up at what might have been the 9 hour mark if Grand hadn't yet erupted, but with the snow and cold and such, it seemed like I wouldn't get out there by the 10 hour mark. So I stayed in, and Grand had a second interval longer than 10 hours.
I've seen several eruptions of Depression the last few days, including a couple of intervals of about 3 hours. Quite a change from my last visits when one Depression eruption per day was about it.
Bison herd at Grand
The walk out to Grand was delayed for a bit by a herd of bison that probably numbered over one hundred. For at least an hour they came down from the hillside behind Grand and Rift and crossed over to the flats to the northwest.
Turns out the bison delay didn't matter, as once again Grand waited two hours from the start of a West Triplet eruption before itself erupting. And once again, there was a considerable period (75 seconds) between the start of Turban and the start of Grand. At the 9m30s mark, Grand had a false pause at least 5 seconds long. So it was a bit surprising that both Vent and Turban didn't quit with Grand.
The odds of walking up onto an eruption of a geyser measured in days is low. The odds of that happening the very first time you walk up to that geyser are even lower. So when you walk up and see what appears to the activity which may lead to an eruption, your first assumption should not be that you are going to see an eruption. Especially when an eruption would lead to an unusually short interval when compared to recent intervals.
So some advice I don't expect to be followed: not only find out what the geyser has been doing recently, but also at least spend a few minutes determining if it really is going to lead to an eruption before you begin a radio play-by-play.
I may or may not have a full Geyser Groupie rant later in the week. That was just a sample.