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Observations for 2019 September 18

This morning there was the thickest fog I've seen in years. It was still forming as we went out before dawn for a Grand eruption. Were surprised to see a large tour on the boardwalk at Castle. Must've been a photo tour, as everyone had their camera on a tripod pointed to the east. Castle had erupted several hours earlier, so assumed they weren't there for that. Over at Grand, the steam looked like Rift was erupting, but had to get to Old Tardy to confirm.

The fog actually cooperated with the Grand eruption. It was fairly clear to the north. Although it was raining enough that umbrellas were needed, we could see the jets of water and Vent easily. The photo tour, for some reason, decided to stay shrouded in the thick fog generated by the runoff channels.

As we left the area, Bulger started erupting. About three minutes later Bulger's Hole suddenly filled with clear water that started surging and got murky. Bulger's Hole was strong and continued about a minute after Bulger ended.

After the One Burst Grand eruption, headed over to Geyser Hil just to check things out, and enjoy the thick fog. It appeared we had missed Aurum and not by much. Over at Beehive, it was totally dead. From there we heard a radio call of Lion erupting. We couldn't see or hear it until we were past Arrowhead Spring. Shortly afterward, noticed a rising steam column over the general fog to the northwest. Had to be Castle, so walked over there and again didn't see anything until up close. The view was interesting, as the sun was visible, but not bright enough for a true backlit steam column. Also noted, as we walked by, that Rift was still erupting two hours after we had seen it earlier.

The fog cleared out, so that for the next eruption, it was clear and a bit breezy. Shortly before noon arrived back out at the Grand Group to find Sput D erupting weakly, while Rift was off but steaming heavily. That ended a few minutes later, and was the last activity seen from that end of the group. Saw several eruptions of Turban, and the last two intervals were well over 24 minutes long, but not long enough to be a Delay by definition.

Grand finally erupted one second after 13:00. The wind and steam cooperated so that it was easy to see the starting events. At around the seven minute mark it looked like Grand was trying to transition into Big Sawmill mode, when instead it quit. The pause was short, and so was the second bursts. The total eruption at that point was just over 8-1/2 minutes. There have been eruptions that short, but this wasn't one of them. The water in the pool was hard to see, but it was there, and it didn't drain. The total duration was just over ten minutes, so we had greedy hopes for a fourth, but Grand didn't even try.

It also didn't try to have an afterburst, even though Vent & Turban continued. It was about 15 minutes before the first splashes were observed, and they weren't all that strong.

Went out before sunset for one final Grand eruption. About 15 minutes after we arrived, was surprised by a West Triplet start. Almost immediately Sput D joined in, and eventually Percolator filled and added to the noise. But as with the other day, all this activity acted more like an indicator, and despite the steamy low light conditions, we could see the pool filling nicely and then Vent overflowing.

Grand started almost immediately, and the burst lasted about 9-1/2 minutes. This seems to be about the upper limit for any chance of a second burst, and fortunately, we got one. When Grand ended, I noticed that West Triplet was also quiet. So it appears that things are changing in the area again.