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Observations for 04 August 2012

After a cool day, I expected a clear night to be cold, and it was. The walkway got slippery by Sawmill, and it was ice by the time I got to Rift. But what I didn't expect was that West Triplet was in overflow.

For about 40 minutes I watched it by Maglight rising to overflow for about 4 to 5 minutes, then drop just enough to stop the overflow. This cycle lasted about 10 to 15 minutes each time. Percolator was quiet, and Grand had another short interval. Another overflow started with Grand, and this time it seemed there was a greater outflow of water. After about 4 minutes, it started thumping, even though the pool itself was quiet. Another minute, and West Triplet started erupting normally.

By moonlight Grand was nice, with the cold making for well defined steam clouds and a hint of moonbow, but it was just one burst.

After I'd just bicycled past the Cathedral on my way to the cabin, a coyote sing-a-long started. Sounded like two different groups yelping and whining and barking at each other, both somewhere in the trees beyond the cabins. It occurred to me as I pedaled that I was headed right toward them. But it all stopped by the time I reached the cabins.

In the morning came a report of Fountain in eruption that was more likely Morning in eruption. The heady fog caused my the cold made it hard to tell which was actually erupting, but the timing of known Fountain eruptions before and after are much more consistent with Morning that with several short Fountain intervals.

Late morning was clear and still cold. There was an occasional slight breeze, and when it was there, a jacket seemed required. Grand had another one of those long Turban delays. This time the overflow from Grand was so heavy that Grand actually "booped", boiled up to about a meter, twice before the overflow subsided. This is the first such activity I've seen in years, although it was quite common in the late 1980s and early 1990s. It's too bad that more geyser gazers weren't around to see it, as there are more than a few who need to realize that they are calling Grand starts too early.

With the cool air and no breeze, Grand's two bursts were both quite tall and impressive. During the start, the steam cloud kept rising faster than the jets, casting shadows onto water column until a higher jet came along.

The later afternoon eruption was similarly picturesque, this time with a rainbow from Vent to Rift, due in part to the breeze blowing the spray to toward the southeast. Unfortunately, there wasn't a second burst to take advantage of the conditions.

Then the third bit of weirdness of the day occurred. As I was walking away I realized I was hearing a familiar noise-- the start of Rift. Except West Triplet had finished an eruption well before I arrived for my two Turban interval wait. I looked, and sure enough, there were the vents of Rift starting to show water. A double-check confirmed that West Triplet was dry and empty as a view from the boardwalk permits. Percolator was also quiet. A truly strange situation, as for at least the last twenty years, as far as I can remember, every eruption of Rift started after about a half-hour of eruption by West Triplet, and usually with Percolator at its noisiest.

I haven't paid much attention to Rift this summer, but was also surprised to see the crack in the rocks to the left of Rift proper spitting and erupting. If it has been active, I've always thought of it as something that comes later, not within moments of the start of Rift. As far as I could tell, the Sputnik area was as dead as it's been all trip.