Observations for 2011 August 12


When the big thrill is seeing a full moonbow in West Triplet's steam, you know the overnight Grand could have gone better.

Once again I came out in time to see West Triplet lead into a Rift eruption. So knew it was going to be a wait. But didn't expect one that long. At around the ten hour mark, got a Turban interval that was down to 16-1/2 minutes, which i took as a sign that an eruption would take place on the next Turban eruption or two. So was a bit surprised when at 13m52s into the next interval Turban started. It was a short, vigorous eruption, which is usually a sign that we've had a bit of a delay, and that Grand wouldn't erupt for at least two more intervals. Just after the moon would be setting, of course.

So when there wasn't any overflow by the 20 minute mark, I wasn't surprised, but curious as to why Turban still hadn't started. Then about a minute later I could hear the runoff pick up. By 27 minute mark, it was a torrent, and the steam over Grand's pool looked like an eruption was imminent. But that all died down a few minutes later, and all ended up getting was a Turban interval well over 32 minutes. Most definitely this was a real delay.

So was a bit of a relief that it was only a two-Turban delay. Could have been worse. The eruption could have been better. When Grand quit at a bit under nine minutes, I expected at least the reward of a second burst, but once a minute passed, it became obvious that one burst was going to be it.

During the wait, around 02:45, suddenly a Ranger car turned on its lights and siren near the Lower Ham's store. This was moderately unusual, as in years past there often wasn't anyone on duty that time of night, and even then rarely have I seen them use a siren at night unless was to make an actual stop. This car kept going, out to the intersection and northwards. The whole time the siren was on, and I could still hear it echoing well north of Biscuit Basin. I assume it was some sort of medical emergency at Madison, or perhaps someone had just provided some fresh meat-loaf for the Lodge.

With Rift out of the way, figured there was always the possibility of a short interval. So while the longer wait made it feel that way, it really wasn't. Grand waited for the end of the West Triplet window, well after West Triplet had quit. If it hadn't been on that Turban, I figure we'd have had to wait another couple of hours. The eruption duration 12m11s, made of for this morning's short, but it still would have been nice to have some pauses in there.

On the other hand, the timing of the eruption was great for the next one. Tonight is the full moon, and the window opens at sunset. This is one of my favorite times, with the full moon rising over the trees behind Rift and the Sawmill Group (as seen from the benches).

A radio call brought some good news: that Rift had started at shortly before the six hour mark. This was good news because I was expecting Rift anyhow, and getting it out of the way early meant that Grand would have one less excuse to have another ten hour interval.

As it was, it needed it. It was another one of those intervals where Grand never showed signs of interest until two Turbans before it finally erupted. Was nice by moonlight, but a second burst would have been even nicer.

During the wait, I finally got to see another eruption of Bulger's Hole. I noticed that Bulger had started a major eruption, and got down there in time to see the hole start to show water. The activity seemed more powerful that three weeks ago, and the vent still makes sounds as it drains. Also, I noticed that the water appeared to be clear as it rose, but turned murky only as the eruption started. Which, I believe, is to be expected.