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Observations for 25 July 2013

I went out to Grand in the pre-dawn hours with the hope of seeing it in the dark, but prepared for a wait until after dawn. The first Turban eruption had all the characteristics of a Vent delay, but in the dark I couldn't tell. One factor making that more likely is that Grand did erupt on the second Turban afterwards. It was also the sixth one burst eruption in a row.

With nothing much to do in the mornings, I came out earlier than necessary to see what Turban might be doing. Turns out it was a good decision. The first partial Turban interval I saw had to have been about 22 minutes, and then we got a 34 minute delay. The pool rose up nicely at around 24 minutes, then sat there for almost 8 minutes before heading back down. The five Turban delay afterwards was a bit more than I'd have liked to have seen, but at least we finally broke the string of one burst eruptions. This was one of those cases where Turban started and Grand went from looking decent to having waves.

As the first burst approached the 8 minute mark, I noticed that the wind had shifted just a bit, and realized that if we did get a second burst, we were going to get wet. And we got the burst, and we did. And it wasn't a quick letdown, but seemed to last for a while as the water droplets drifted our way instead of dousing the crowd down by Rift, like it did for the first burst.

There were reports that East Sentinel had had a couple of major eruptions during the day. So after Grand I decided to go look for myself. What I found didn't look much different than what I'd seen earlier. I was disappointed that there wasn't any evidence of catch basins that contained water that shouldn't be there, the way you can tell Fan & Mortar have been active the next day by the wet areas on Mortar. But I did see a nice surge that had water filling the crater while the surging reached about 6 feet and occasionally splashed over the near edge of the crater. The next two cycles were not as big.

We also started getting afternoon sprinkles today, after most of a week of dry. Fortunately, there wasn't any reason to be out and about at the times we got the short showers, so I didn't get wet.

The evening Grand was another one of those cases of going out with the hope of short interval, but prepared for long. Because of the time, this preparation meant carrying some jackets and even a flashlight. Off to the north we could hear the clouds rumbling as we waited. But it wasn't a short wait.

But we did get one of the best examples of a "boop" from Grand that's I've seen in years. The pool came up to completely full, where the ridges were completely gone, but there were not waves. And then just sat there for the better part of a minute. Then the little bubbling over the vent that Grand always has during into a boil about a foot high. And then nothing, for a good ten seconds. Finally we got another boil, and almost got a blue bubble from Grand as the eruption started explosively the way some Grand-initiated eruptions can do.

There are at least a couple of gazers who really like to announce geyser starts before the actual start who are someday going to get caught by a boop that becomes a delay, and have to retract their report. And it'll serve 'em right, as I've been commenting to people who do that sort of things to watch out. (Beehive in another popular target.)

And we got another one burst. Since my server is down (or gone), I can't get at all the numbers I need, but the average is definitely not getting better. At one point last week we were at 70% one burst eruptions, but thanks to a series of two burst eruptions, that actually got down to about 55%. It's now probably back in the 70% range. This means that most days there is only one Grand eruption with multiple bursts, and our 4 day/4 bursts Grand day yesterday isn't that unlikely. Enjoy the second bursts while you can.