geysers.org

With all the shorter Grand intervals recently, I decided that 13 hours was a good interval for a double overnight interval. The overnight eruption was caught on the webcam, and my projected arrival time didn't change.

A nice clear morning, the first one of this visit. Got out to Grand in time to see heavy overflow, followed by a long Turban eruption, it appears that we had a Turban Delay interval. Four Turban eruptions later, Grand filled and never receded, giving us a nice, backlit One Burst Eruption. West Triplet started to erupt right after Vent & Turban quit. Didn't stick around for the end or a Rift eruption, as it was time to try the Lower Store's breakfast.

2026-May-25 : 09:27:12 T1Q

 09:26:56	Vent Ovfl	-0m16s
 09:27:01	Turban	-0m11s
 09:27:09	Boop	-0m03s
 09:27:12	B1	--- d=11m50s
 09:30:31	Vent	3m19s
 09:39:02	P1	11m50s
 09:39:43	V&T Quit	12m31s

				     	ΣD=11m50s
	* * * * *
 08:11:02			d=05m04s 	
 08:29:04	Int: 18m02s	d=04m16s 	
 08:48:48	Int: 19m44s	d=03m59s 	
 09:07:01	Int: 18m13s	d=04m09s 	
		     Turban: 20m00s

Then went out to catch Artemisia, which hadn't been seen since yesterday morning. Got down to Fan & Mortar and the activity had changed. Now Fan's Gold and High vents were active, while Main and Mortar's Bottom vent was quiet. High was erupting at least four meters high at times, and if Angle had also been active, it would have looked like an eruption was imminent. As it wasn, the activity died down.

Headed for Artemisia again, and this time got delayed by East Sentinel. The vent was dead calm, with only occasional slight ripples over the locations of the vents along the back side. There was considerable runoff, and it looked like it might be fluctuating. I took some video, and that's when Artemisia started to erupt.

So I headed back to Fan & Mortar, where High and Gold continued to look good. At some point Angle joined in, and again there was the appearance of the start of an eruption. For the next half-hour or so, those vents could cycle from quiet to quite strong.

By mid-afternoon our good weather had deteriorated to the point where I decided I'd better bring a jacket, which I ended up putting on shortly after I arrived at Grand.

West Triplet was in eruption as I was tying up my bike, and Turban erupted right after I arrived. Not surprised when Rift started about a half hour later. That eruption lasted well over 1-3/4 hours. At about 1-1/4 hours in, Turban had a Delay Eruption interval.

After that, the durations and intervals of the Turban eruptions got noticeably shorter, until the fifth eruption ended up being another Turban Delay interval. For this next series, the intervals were even shorter, with all but one under 17 minutes. They all seemed to have early fills of Grand's pool, which would then drop just before Turban started to erupt,

Then on the fifth interval, Grand was full at around 11-1/2 minutes and started having waves. These built up such that at 13 minutes, Turban started to erupt. Then Vent started to overflow, and finally a half minute later Grand started after a series of Boops. This Turban interval preceding Grand is one of the shortest I've ever seen.

Once again we had a One Burst Grand eruption, but for the last few minutes, the clouds parted and the eruption was illuminated by the setting sun. The duration was just over ten minutes, and despite being short, Vent & Turban quit.

2026-May-25 : 20:11:22 D5/D5/T1Q

 20:10:39	Turban	-0m43s
 20:10:46	Vent Ovfl	-0m36s
 20:11:15	Boop	-0m07s
 20:11:22	B1	--- d=10m06s
 20:13:33	Vent	2m11s
 20:21:28	P1	10m06s
 20:22:22	V&T Quit	11m00s

				     	ΣD=10m06s
	* * * * *
 15:13:41ie	West Triplet
 15:19:01			d=01m54s 	
 15:35:33	Int: 16m32s	d=03m25s 	
 15:47:04	Rift
 15:55:24	Int: 19m51s	d=03m22s 	
 16:14:40	Int: 19m16s	d=03m54s 	
 16:34:03	Int: 19m23s	d=03m42s 	
 17:06:38	Int: 32m35s	d=03m38s  D0	
 17:24:51	Int: 18m13s	d=03m11s  D1	
 17:42:29	Int: 17m38s	d=03m06s  D2	
 18:01:44	Int: 19m15s	d=02m31s  D3	
 18:19:30	Int: 17m46s	d=03m08s  D4	
 18:50:14	Int: 30m44s	d=04m11s  D5/D0	
 19:07:42	Int: 17m28s	d=03m06s  D5/D1	
 19:24:25	Int: 16m43s	d=03m28s  D5/D2	
 19:41:10	Int: 16m45s	d=03m45s  D5/D3	
 19:57:38	Int: 16m28s	d=03m08s  D5/D4	
		     Turban: 13m01s

Just as several of us walked up to our bikes, Castle started to erupt. By then the sun was even lower, and Castle was nicely illuminated. We were prepared to watch the eruption, but it was a minor that lasted less than four minutes.

Overnight the webcam picked up a Grand eruption at just over the six hour mark. So was out at dawn just in case there was another six hour interval. There wasn't, and instead ended up waiting over four hours through a couple of West Triplet eruptions. The second one resulted in the start of Rift. The wait started out overcast and foggy but above freezing. The sun tried to come out, but never really did.

It was a typical non-delay type of long wait. During the last couple of hours of the wait, Turban's eruption intervals got shorter. There were several below 17 minutes, and the Turban eruption duration prior to Grand's eruption was less than two minutes long.

2026-May-24 : 10:51:26 T1Q

 10:51:05	Vent Ovfl	-0m21s
 10:51:11	Turban	-0m15s
 10:51:16	Boop	-0m10s
 10:51:26	B1	--- d=11m02s
 10:53:58	Vent	2m32s
 11:02:28	P1	11m02s
 11:03:22	V&T Quit	11m56s
 11:09:47	V&T Restart	18m21s

				     	ΣD=11m02s
	* * * * *
 06:54:57			d=03m54s 	
 07:12:34	West Triplet d=36m12s
 07:15:14	Int: 20m17s	d=04m08s 	
 07:34:24	Int: 19m10s	d=03m19s 	
 07:51:06	Int: 16m42s	d=02m39s 	
 08:09:25	Int: 18m19s	d=03m48s 	
 08:27:59	Int: 18m34s	d=03m36s 	
 08:47:23	Int: 19m24s	d=03m54s 	
 09:07:26	Int: 20m03s	d=03m58s 	
 09:26:48	Int: 19m22s	d=03m22s 	
 09:43:32	Int: 16m44s	d=03m27s 	
 09:59:58	Int: 16m26s	d=03m49s 	
 10:07:19	West Triplet d>1h05m
 10:17:17	Int: 17m19s	d=03m04s 	
 10:34:24	Int: 17m07s	d=01m58s 	
 10:44:23	Rift
		     Turban: 16m47s

During the last hour of the wait the showers started, and then there were showers all afternoon, so it seemed like a good time to do some app bug fixing.

After an afternoon of occasional thundershowers, headed out to cool gray skies. The hour-and-a-half wait was uninteresting until the end. At around the 18 minute mark after the previous Turban eruption, Grand's pool, which had been looking poor, started to rise. For the next ten minutes the pool was at or near full, but never quite good enough. Then the pool surpassed the level from the previous fills. Vent overflowing and a series of boops and then we got another One Burst Eruption. As before, it seemed like Grand slowed down around the eight minute mark, and long ago it would have stopped at that point. Instead the jetting picked up a bit, and lasted another three minutes.

2026-May-24 : 18:48:10 D0/T1Q

 18:48:00	Vent Ovfl	-0m10s
 18:48:02	Boop	-0m08s
 18:48:07	Turban	-0m03s
 18:48:10	B1	--- d=11m22s
 18:50:35	Vent	2m25s
 18:59:32	P1	11m22s
 19:00:10	V&T Quit	12m00s

				     	ΣD=11m22s
	* * * * *
 16:42:01			
 17:02:54	Int: 20m53s	d=04m06s 	
 17:21:29	Int: 18m35s	d=03m59s 	
 17:41:32	Int: 20m03s	d=03m43s 	
 18:00:31	Int: 18m59s	d=03m23s 	
 18:18:13	Int: 17m42s	d=03m17s 	
 18:55:18	West Triplet
		     Turban: 29m54s

Shortly after Grand started, West Triplet also began to erupt. It seems that this year West Triplet can recover from Rift within one of Grand's eruption intervals.

Went out to Geyser Hill to enjoy the nicest weather since our arrival, on the off chance Beehive might eruption. It didn't, so I headed in to reconfigure and go back out to Grand.

Saw Turban erupting as I was tying down my bike. Fortunate, as this was followed a Turban Delay interval of over 32 minutes. That Turban eruption coincided with the eruption of Beehive.

An hour later, a visitor noticed a bear ambling across the flats to the north. It passed by Beauty, crossed the boardwalk and then headed off into the trees.

Grand finally had the One Burst Eruption after seven Turban eruption intervals ending with another Delay Interval. The wind was strong from the south and the start didn't seem that tall.

2026-May-23 : 12:22:52 D7/D0/G1C

 12:22:50	Boop	-0m01s
 12:22:52	B1	--- d=10m11s
 12:23:52	Turban	1m00s
 12:25:54	Vent	3m01s
 12:33:03	P1	10m11s
Vent & Turban continue

				     	ΣD=10m11s
	* * * * *
 09:27:11			
 09:59:10	Int: 31m59s	d=04m50s  D0	
 10:17:03	Int: 17m53s	d=04m10s  D1	
 10:37:09	Int: 20m06s	d=03m45s  D2	
 10:57:04	Int: 19m55s	d=04m01s  D3	
 11:17:21	Int: 20m17s	d=03m35s  D4	
 11:35:54	Int: 18m33s	d=03m39s  D5	
 11:53:21	Int: 17m27s	d=03m40s  D6	
		      Grand: 29m31s

Late evening it was back out to Grand with the expectation of a long wait. Had extra layers and the light, just in case. Turned out it wasn't necessary, as I only had to wait for one Turban eruption interval. At the start of that interval, West Triplet began to erupt, and Castle had a minor eruption during that time. Grand's pool had a nice, steady fill, and the One Burst Eruption without any Delay.

At around the 8-1/2 minute mark, Grand slowed down, acting like every jet was going to be the last one of the burst. It wasn't even a Big Sawmill mode. Then the activity picked up once any chance of a second burst was gone.

2026-May-23 : 18:44:37 G1Q

 18:44:31	Vent Ovfl	-0m06s
 18:44:34	Boop	-0m03s
 18:44:37	B1	--- d=10m23s
 18:44:48	Turban	0m11s
 18:47:46	Vent	3m09s
 18:55:00	P1	10m23s
 18:55:59	V&T Quit	11m22s
 19:05:42	V&T Restart	21m05s

				     	ΣD=10m23s
	* * * * *
 18:24:27			
 18:28:49ns	West Triplet
 19:17:01	Rift
		      Grand: 20m10s

I then waited for the start of Rift. It took its time, but 45 minutes into the West Triplet eruption, suddenly Rift started steaming and within a few minutes was in eruption. I didn't wait for West Triplet to end.

Instead went down basin for the first time this visit, and spent 40 minutes watching Fan & Mortar. There was no change during that time. River Vent was steaming the whole time. Bottom Vent was splashing strongly, but there was little runoff. Main Vent was strong and noisy, with some bursts and splashing well above the back rim, with heights up to two meters.

Turns out coming back in last night was a good idea. Grand erupted well after midnight with an interval of over eleven hours, with a Rift eruption during that time.

I didn't know that when I went out in the morning. Grand was in overflow, and Turban started shortly after I arrived. The duration was fairly short. Castle started a major eruption at the same time.

Grand had a One Burst Eruption with the next Turban eruption, with West Triplet starting near the end. I decided to stick around to get the duration, and make sure Rift didn't erupt. Turns out Rift did erupt, giving it an interval of less than 10 hours.

2026-May-22 : 08:09:30 T1Q

 08:09:12	Turban	-0m18s
 08:09:27	Vent Ovfl	-0m03s
 08:09:30	B1	--- d=11m18s
 08:12:32	Vent	3m02s
 08:20:48	P1	11m18s
 08:21:29	V&T Quit	11m59s
 08:42:38	V&T Restart	33m08s

				     	ΣD=11m18s
	* * * * *
 07:50:40			d=03m24s 	
 08:22:07ns	West Triplet
 08:55:24	Rift
		     Turban: 18m32s

Returned to the cabin, then decided to walk out via Geyser Hill to wait for Uncertain. I figured that there was a good chance that Beehive might be active in the next few hours. That way once the wait in the Sawmill Group was over, I could hang around on Geyser Hill for a while.

The wait for Uncertain wasn't long. Sawmill started shortly after I arrived, and that's when Uncertain started to splash heavily. Within ten minutes, it erupted, and both it and Sawmill ended their eruptions at the same time.

As usual, it was windy on Geyser Hill, and waited for about 45 minutes. Made the mistake of not waiting next to Aurum, as it erupted during that time.

Went back to the cabin for lunch, figuring I'd be out in the wind all afternoon at Grand, and could run out, as usual, for Beehive. Turns out no one called out the Indicator, and I only noticed the entry for the Indicator eight minutes after it started.

With three of the last four Grand intervals near six hours (the fourth was near twelve) I had to go out at the six hour mark. Over the next 2-1/2 hours, saw a mostly undistinguished series of Turban eruptions. The intervals slowly dropped from well over twenty minutes to less than eighteen. Then we got a Turban Delay interval.

Fortunately, Grand was able to erupt during that Delay, and it even had two bursts. The pool drained after the second burst, and there was never water visible after that.

2026-May-22 : 16:32:27 D0/G2C

 16:32:23	Boop	-0m04s
 16:32:27	B1	--- d=08m21s
 16:32:34	Vent Ovfl	0m07s
 16:32:47	Turban	0m20s
 16:35:13	Vent	2m46s
 16:40:48	P1	8m21s d=23s
 16:41:11	B2	8m44s d=01m01s
 16:42:12	P2	9m45s
Vent & Turban continue

				     ΣB=09m22s	ΣD=09m45s
	* * * * *
 14:10:10			d=03m57s 	
 14:30:50	Int: 20m40s	d=04m13s 	
 14:50:30	Int: 19m40s	d=03m30s 	
 15:09:22	Int: 18m52s	d=03m38s 	
 15:28:00	Int: 18m38s	d=03m26s 	
 15:46:05	Int: 18m05s	d=03m14s 	
 16:03:48	Int: 17m43s	d=03m30s 	
 16:32:01	West Triplet	d=37m00s
		      Grand: 28m39s

During the eruption, down by the Grand sign, there was a ground of people taking selfies. In turn, each one would step off the boardwalk and strike a stupid pose, as if they had accomplished something dramatic.

Near the start of Grand's eruption, West Triplet started. I stuck around to catch the end, just in case Rift had an even shorter interval. But while the West Triplet eruption seemed a bit long, it didn't trigger Rift.

As I was leaving, Bulger had its second observed major eruption of the day.

Overnight we got at least an inch of wet slushly snow. By dawn, there were still light snow showers, and a strong wind from the northwest. The walkway wasn't as slippery as I expected, probably because it was slush instead of ice.

Uncertain was gurgling with occasional splashes, so I spent about twenty minutes watching it, but nothing much changed during that time. So went over to Grand. Rift's runoff channel was snow-free, indicating it probably erupted in the last few hours. Arrived just in time to catch the start of a Turban eruption. That was followed by an almost 30 minute long Turban Delay interval.

With the wind, most of the steam was being pushed to the south so that Grand's pool was easily visible. Three Turban eruption intervals later, Grand filled nicely. Turban started, and then it appeared Vent was overflowing. It took Grand nearly a minute to start erupting, after a series of boops. The wind was still making the One Burst Eruption visible.

2026-May-21 : 08:02:16 D3/T1C

 08:01:23	Turban	-0m53s
 08:01:39	Vent Ovfl	-0m37s
 08:02:10	Boop	-0m06s
 08:02:16	B1	--- d=09m29s
 08:04:30	Vent	2m14s
 08:11:45	P1	9m29s
Vent & Turban continue

				     	ΣD=09m29s
	* * * * *
 06:41:47			d=03m06s 	
 07:11:09	Int: 29m22s	d=04m20s  D0	
 07:28:27	Int: 17m18s	d=03m46s  D1	
 07:44:58	Int: 16m31s	d=03m28s  D2	
		     Turban: 16m25s

Following the eruption, stopped in at Sawmill and Uncertain again. Sawmill's pool level was high, and Uncertain was having strong splashes. Then Sawmill started, quickly overflowing as Uncertain's activity seemed to die down. At that point I decided to head back in to warm up and dry out.

With Grand having several short intervals since we arrived, decided I should not delay my arrival. The weather was dry, but windy. I had just passed West Triplet when Grand boiled up, starting the One Burst Eruption. As with this morning, the best view was at the north.

2026-May-21 : 14:16:19 G1Q

 14:16:19	B1	--- d=11m17s
 14:16:27	Turban	0m08s
 14:19:21	Vent	3m01s
 14:27:36	P1	11m17s
 14:28:29	V&T Quit	12m09s
 14:40:06	V&T Restart	23m47s

				     	ΣD=11m17s
	* * * * *
 14:26:39	West Triplet	d=26m13s

West Triplet started near the end of the Grand eruption. I waited to see if Rift might start, but West Triplet had a duration less than necessary to trigger Rift.

With all the recent shorter intervals for Grand, I decided it was better to be there early. It was just before sunset, with a clear sky and a cold wind coming from the north. I arrived to find Grand in a heavy overflow, most likely a Turban Delay interval. West Triplet had also just ended an eruption.

Four Turban eruption intervals later, there was a second Delay interval. At that point, it was dark and frost was starting to form on the boardwalks. I decided it was time to head back in.

2026-May-21 : 20:12:35

 20:22:42			d=04m51s 	
 20:40:01	Int: 17m19s	d=03m46s 	
 20:59:42	Int: 19m41s	d=03m55s 	
 21:20:06	Int: 20m34s	d=03m33s 	
 21:48:57	Int: 28m51s	d=04m25s  D0	

Woke up shortly before the alarm, and within a minute or two got the Beehive Indicator call. This time I only made it to the Firehole River bridge before I heard the roar of Beehive's eruption. Did get as far as Anemone (both vents were erupting). Also, Little Squirt was in eruption, and the alter ground near the boardwalk was steaming heavily.

Went back to the cabin to reconfigure, then headed out to Grand as it was almost 15 hours since the eruption we saw yesterday. Arrived to find Grand in overflow. Turns out that, based on the secret NPS time, I probably saw first overflow.

For the next couple of hours, it was a series of undistinguished Turban eruptions. Finally, West Triplet started to erupt, and eruption that lasted over an hour. During the middle of that eruption, I again saw slight steam coming from the location of East Triplet. Finally, after about fifteen minutes of heavy steaming, Rift began its eruption.

That eruption only lasted about 46 minutes. Two Turban eruption intervals later, Grand had its first good overflow, and we got a steamy but backlit One Burst Eruption.

2026-May-20 : 10:10:04 G1Q

 10:10:00	Boop	-0m03s
 10:10:04	B1	--- d=10m59s
 10:12:58	Vent	2m53s
 10:21:04	P1	10m59s
 10:22:09	V&T Quit	12m04s

				     	ΣD=10m59s
	* * * * *
 06:33:35			d=43s 	
 06:49:49	Int: 16m14s	d=03m45s 	
 07:11:29	Int: 21m40s	d=04m26s 	
 07:31:11	Int: 19m42s	d=03m56s 	
 07:52:20	Int: 21m09s	d=04m15s 	
 08:07:49	West Triplet d=01h04m 
 08:12:28	Int: 20m08s	d=04m29s 	
 08:31:56	Int: 19m28s	d=03m54s 	
 08:49:27	Rift d≈46m
 08:50:41	Int: 18m45s	d=04m18s 	
 09:09:13	Int: 18m32s	d=03m40s 
 09:12:22	end West Triplet	
 09:28:32	Int: 19m19s	d=02m59s 	
 09:46:36	Int: 18m04s	d=03m20s 	
		      Grand: 23m28s

When to return to Grand was an open quesiton. I didn't want to go too early, as these long waits in the cold and wind are tiresome, but didn't want to miss a short interval. Settled on getting out at around the 6-1/2 hour mark. So Grand erupts at just over six hours. I'd just finished something to eat and was getting properly configured.

Instead I went out to wait for Uncertain. Sawmill had a short, no overflow eruption while I was watching and waiting for West Triplet to quit, and see if Rift would start. It didn't. Then Sawmill starts another eruption about 45 minutes later, this time getting strong and overflowing.

By this time Uncertain had been splashing and gurgling nicely, so three minutes later, it also erupted.

At that point it was getting colder and windier, and it looked like the precipitation could start soon.

After last night, Grand erupted at dawn with a reasonable interval. The temperature was listed at 19. Rift erupted soon after, and had quit by the time I got out just before 09:00. The temperature was still a couple of degrees below freezing, and there were quite a few icy runoff channels around Grand.

I also noticed that it was nicely steamy. There was nothing coming from the hillside with the sputs like Sput D and Sputnik. But there was a slight whisp of steam coming from the location of East Triplet.

Afterwards I went to look around Geyser Hill, where there were still a lot more frozen runoff channels, even at 10:00. At around 11:40, I decided I wanted to get over to Grand, and left. I was at the bridge when the "water in the Indicator" call came out. So I reversed and watched the eruption. After a morning with a consistent wind direction, it shifted three minutes into the eruption so that the boardwalk got a soaking.

A quick reconfigure at the cabin, and it was out to Grand. Arrived to find Turban in what was probably a Delay Interval, based on the Turban eruption duration and the behavior during the following interval.

Six Turban eruptions later, late in a West Triplet eruption, we got our second Turban Delay eruption. Four more Turban eruptions and we got a third Delay. Grand finally erupted two more Turban intervals later, on an interval of sixteen minutes.

Grand started with a large boop, and there were two bursts. West Triplet followed the Grand eruption, and there was a report of Rift erupting with a 11 hour interval.

2026-May-19 : 16:30:02 D4/D2/G2Q

 16:29:58	Boop	-0m04s
 16:30:02	B1	--- d=10m57s
 16:32:54	Vent	2m52s
 16:39:11	P1	9m09s
 15:39:53	B2	0m42s
 15:40:59	P2	1m06s
 15:41:36	V&T Quit
				     	ΣD=10m15s

 	* * * * *
 12:30:30			d=04m43s 	
 12:48:21	Int: 17m51s	d=03m24s 	
 13:07:31	Int: 19m10s	d=03m46s 	
 13:25:18	Int: 17m47s	d=03m13s 	
 13:44:47	Int: 19m29s	d=03m11s 	
 14:03:23	Int: 18m36s	d=03m38s 	
 14:18:22	West Triplet
 14:34:42	Int: 31m19s	d=04m56s  D0	
 14:52:52	Int: 18m10s	d=02m49s  D1	
 15:08:47	Int: 15m55s	d=03m38s  D2	
 15:25:38	Int: 16m51s	d=03m11s  D3
 15:56:19	Int: 30m41s	d=4m22s	  D4/D0
 16:14:18	Int: 17m59s	d=3m23s   D4/D1
 		     Turban: 15m44s

Following Grand we only had to wait a few minutes to have an eruption of Uncertain, and then it was time to get out of the wind and cold.

I'd checked the road conditions before we left, and our route to Yellowstone appeared to be a bit wet, but otherwise open. That changed, because when we approached the last exit to Laramie, we encountered a line of trucks parked along I-80, because the highway to the west was closed. That was not good.

We fueled up and then I took a look at the road conditions map. Not only was I-80 closed, but so was US-30. There was, however, no indication that Wyoming-34 was closed. It branches off of US-30 about ten miles north of Laramie, and that's where the closure started. Decided to risk the ten mile drive, as the alternative was to head east to Cheyenne and then head north on I-25. If Wyo-34 was open, it would make the alternate route less painful.

It was open, but pretty slushy for much of the fifty miles. Then it was north on I-25, which was wet, but not slippery or slushy most of the way, so I was able to drive at the 80mph speed limit.

That got us to Casper, where the exit we'd intended to use to fuel up was blocked due to a collision. Fortunately, the closure was gone by the time we went back on the way to an alternate route. At that point, the conditions improved dramatically, and except for slush at the summit of Togwotee Pass, the road was clear.

So we checked in about two hours later than expected, and as we walked from the front desk of the Lodge to my truck parked by the cabins, we heard the "water in Beehive's Indicator" call. We had to go out to Geyser Hill without extra layers, and Geyser Hill was colder and windier than usual. But despite that, it was a nice welcome back.

Later we went out to Grand hoping for an eruption, but after two hours of non-descript Turban eruptions, we gave up. By then it was almost 22:00, and dark, and cold. The temperature was around 28, and windy.