Observations for 2018 October 15


Today started like yesterday. Temperature was in single digits when we arrived at Norris, and there were a couple of tour buses in the parking lot. Unlike yesterday, the tours were visiting the Back Basin instead of Porcelain Basin.

Set up on the upper platform again in anticipation of it eventually getting sunny, although that turned out to be several hours away. New Crater/Steamboat was more active than yesterday, but during those cloudy hours, it never had a good minor. (A good minor is one where it's time to use the camera.) Eventually clouds and fog broke and it started to warm up. Around noontime, moved down to the lower platform, as I can't tell what the South Vent is doing from the upper.

The activity did pick up a little, but it wasn't until 13:27 that it had a minor that showed that there was eruptive potential. That was followed four minutes later by another one, and then they started coming about ten to twelve minutes apart. All during this time the activity of the minors was concentrated in the North Vent, with the South not quite as strong as before other eruption.
But at 14:11, a minor started and built, and at 14:12, we got the eruption.

Both vents climbed slowly to full height, and were clean for the first minute or so. Then the fun began. North turned reddish-brown, and began spewing out rocks. Large rocks thrown to great heights. More rocks than I've seen in all of the five previous eruptions. After a few minutes, the water there seemed so thick that the North Vent was only erupting 10 or 20 feet high.

When I was down at the runoff, I saw (and recorded) a large chunk of reddish mud plopping onto walkway. Surprised me, because I didn't think rocks would be flying that far, so it was probably thrown there by the torrent of water coming down the channel.

There was very little wind, and what little there was had the steam column drifting away from us. Because of this, later in the eruption the condensing steam made for nice rainbows which seemed to appear on either side depending on where the wind was drifting.

Ended the day by going out at sunset for one last One Burst Grand. Got there in time to see a Turban delay, so it was a Two-Turban Delayed One Burst Grand eruption that we eventually saw. The temperature was about 26°F, which was about the same temperature at which we saw New Crater/Steamboat last week.