Last Known Eruption
32y 323d 14h 44m ago

Latest Eruptions

Eruption DurationInterval
10 Jan 1992 @ 1605 ie

Interval Statistics

Not enough entries to compute statistics.

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
36429 17 Aug 2024 @ 0640 --- RMichaels Water level at least 10" below the top of the orange bacteria ring. Yesterday's Grotto Marathon probably continued well into the night/early morning. Bijou was also off when I rode past the Giant platform.
35243 16 Jun 2024 @ 1155 --- Tara Down ~1.5' below top of orange bacteria, steady bubbling
34444 05 May 2024 @ 1358 --- SantaFe108 Dropping and bubbling, Marathon in progress.
33472 27 Dec 2023 @ 0959 --- aferrara water down 8-12", boiling gently over vent
26690 27 Jun 2023 @ 0554 --- JimS Very low
26151 08 Jun 2023 @ 0819 --- aferrara Water level down about 6" from top of bacterial mat rim. Boiling over vent
26127 07 Jun 2023 @ 1547 --- SantaFe108 Dropping while bubbling.
25377 10 May 2023 @ 0855 --- aferrara Boiling intermittently, water about 18" below rim
25298 30 Apr 2023 @ 1645 --- SantaFe108 Water level is lowering and bubbling.
20318 06 Nov 2021 @ 0855 --- aferrara Water level low, steady stream of bubbles in center.
19599 16 Sep 2021 @ 0811 --- CrisG Pool low. water at yop of bacterial ring. Grotto still IE.
18445 16 Jul 2021 @ 0803 --- JimS Pool low. Grotto marathon overnight.
18315 09 Jul 2021 @ 0558 --- JimS Pool low but recovering from the Grotto marathon.
18213 01 Jul 2021 @ 0601 --- JimS Pool low. Was a Grotto marathon overnight.
18099 26 Jun 2021 @ 0546 --- JimS Pool low, was a grotto marathon overnight.
18028 22 Jun 2021 @ 1952 --- CrisG pool has dropped since last observation. water now 2" above orange bacteria.
18027 22 Jun 2021 @ 1525 --- CrisG pool high, up to bottom of sinter rim
17898 19 Jun 2021 @ 0553 --- JimS Pool very low.
15647 19 Aug 2020 @ 0710 --- RMichaels 6 inches below the top of the orange bacteria inside the pool and lightly bubbling.
12398 07 Jul 2019 @ 1043 --- ldgordon Pool seems to be about a foot below the top of the bacteria line
11563 04 Jun 2019 @ 0845 --- User34 Down about 1/3 of the way to the vent, bubbling.
10790 25 Dec 2018 @ 1550 --- Janet Jones Looks like it recently dropped 6” or so
10124 09 Sep 2018 @ 1219 --- EmilyW Down a bit and grotto has been off for a long time. Likely has had a marathon
9289 25 Jul 2018 @ 0617 --- JimS Down about 4 inches.
8829 21 Jun 2018 @ 0620 --- JimS Down about 6 inches.
8053 02 May 2018 @ 0920 --- WillBoekel 2-3 inches from overflow
8049 01 May 2018 @ 0853 --- Micah Kipple Almost at ovf
8026 28 Apr 2018 @ 0637 --- Micah Kipple It was slightly [read: barely] down about an inch with steady ebullition. Perhaps suggesting the Grotto last night was a weak marathon. But put a big (?) on that interpretation.
7534 29 Sep 2017 @ 0750 --- Kitt B pool down about 6 inches
3191 22 Jun 2016 @ 1425 --- David water level down about a foot. orange bacteria ring dried and cracking indicating low water level for some time. see photo: https://www.flickr.com/photos/ujelang/27447783513/in/dateposted-public/
3192 30 Sep 2013 @ 1023 --- David Water in pool brim full, nearly overflowing. see photo: https://www.flickr.com/photos/ujelang/28028231296/in/dateposted-public/ [exif time on pacific time, not mtn).
16705 22 Aug 1998 @ 2055 --- JarnoO a few inches below cyanobacteria's lower edge
16703 21 Aug 1998 @ 0855 --- JarnoO down to lower ledge of cyanobacteria
14323 08 Jun 1995 @ 1830 --- JarnoO down >1'
12719 18 Aug 1994 @ 0225 --- JarnoO down 1'+
12666 14 Jun 1994 @ 0938 --- JarnoO down.
12305 22 Aug 1993 @ 1000 --- JarnoO low @ 1000
12299 20 Aug 1993 @ 0600 --- JarnoO low at 0600
12296 18 Aug 1993 @ 0930 --- JarnoO low at 0930
12294 14 Aug 1993 @ 0805 --- JarnoO low 0805
12142 08 Feb 1993 @ 0000 08 Feb 1993 @ 2359 JarnoO bubbling
12138 07 Feb 1993 @ 0957 --- JarnoO down.
5443 10 Jul 1992 @ 1330 --- JarnoO very low
5168 09 Apr 1992 @ 0000 09 Apr 1992 @ 2359 JarnoO down.
5046 03 Mar 1992 @ 0800 --- JarnoO 0800 low
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