Last Known Eruption
2d 14h 38m ago

Latest Eruptions

Eruption DurationInterval
23 Nov 2024 @ 0658 ie wc2d 18h 23m
20 Nov 2024 @ 1235 ie wc1h 23m < d < 1h 48m23h 45m
19 Nov 2024 @ 1250 ie wc1d 5h 54m
18 Nov 2024 @ 0656 ie wc23h 16m
17 Nov 2024 @ 0740 ie wc6h 25m
17 Nov 2024 @ 0115 wc1d 12h 22m
15 Nov 2024 @ 1253 ns wc7h 34m
15 Nov 2024 @ 0519 ns wc9h 11m
14 Nov 2024 @ 2008 wc2h 17m 7h 54m
14 Nov 2024 @ 1214 ie wc2h 4m < d < 2h 41m6h 50m
14 Nov 2024 @ 0524 ns wc1h 36 < d < 1h 436h 20m
13 Nov 2024 @ 2304 wc1h 34m 6h 16m
13 Nov 2024 @ 1648 wc1h 8m 3h 44m
13 Nov 2024 @ 1304 wc1d 22h 4m
11 Nov 2024 @ 1500 wc23h 39m
10 Nov 2024 @ 1521 ie wc1d 5h 11m
09 Nov 2024 @ 1010 ie wc1d 15m
08 Nov 2024 @ 0955 ie wc22h 15m
07 Nov 2024 @ 1140 wc2d 15m
05 Nov 2024 @ 1125 ie wc3d 19h 56m
01 Nov 2024 @ 1629 ie wc5h 9m
01 Nov 2024 @ 1120 wc17h 43m
31 Oct 2024 @ 1737 ie wc4h 37m
31 Oct 2024 @ 1300 ie wc1h18m < d < 1h41m1d 3h 13m
30 Oct 2024 @ 0947 ie wc2d 2h 38m
28 Oct 2024 @ 0709 ie wc18h 26m
27 Oct 2024 @ 1243 wc19h 56m
26 Oct 2024 @ 1647 ns wc1d 42m
25 Oct 2024 @ 1605 ns23h 59m
24 Oct 2024 @ 1606 ns wc4h 36m
24 Oct 2024 @ 113021h 55m
23 Oct 2024 @ 1335 ie wc14h 5m
22 Oct 2024 @ 2330 ns wc6h 56m
22 Oct 2024 @ 1634 wc6h 20m
22 Oct 2024 @ 1014 wc5h 9m
22 Oct 2024 @ 0505 ns wc5h 51m
21 Oct 2024 @ 2314 ns wc4h 30m
21 Oct 2024 @ 1844 ns wc15h 37m
21 Oct 2024 @ 0307 ns wc14h 37m
20 Oct 2024 @ 1230 wc2h 56m 22h 54m
19 Oct 2024 @ 1336 wc1h24m < d < 1h31m21h 31m
18 Oct 2024 @ 1605 wc5h 27m
18 Oct 2024 @ 1038 wc1h 7m < d < 1h 13m2d 16h 30m
15 Oct 2024 @ 1808 wc~1d 11h 30m 5h 35m
15 Oct 2024 @ 1233 ns15h 47m
14 Oct 2024 @ 2046 ns wc8h 14m
14 Oct 2024 @ 1232 ie wc20h 30m
13 Oct 2024 @ 1602 ie wc23h 19m
12 Oct 2024 @ 16436h 59m
12 Oct 2024 @ 0944 wc17h 44m
11 Oct 2024 @ 1600 wc≥1h56m6h 44m
11 Oct 2024 @ 091620h 48m
10 Oct 2024 @ 1228 ie wc1d 58m
09 Oct 2024 @ 1130 ie1d 22h 33m
07 Oct 2024 @ 1257 wc20h 34m
06 Oct 2024 @ 1623 ie wc4h 18m
06 Oct 2024 @ 1205 wc4h 5m
06 Oct 2024 @ 0800 ie wc18h 47m
05 Oct 2024 @ 1313 wc5h 44m
05 Oct 2024 @ 0729 ie15h 45m
04 Oct 2024 @ 1544 wc1d 2h 0m
03 Oct 2024 @ 1344 ie1d 5h 4m
02 Oct 2024 @ 0840 ie18h 54m
01 Oct 2024 @ 13461d 2h 34m
30 Sep 2024 @ 111217h 15m
29 Sep 2024 @ 1757 ie8h 42m
29 Sep 2024 @ 091521h 18m
28 Sep 2024 @ 1157 ie18h 6m
27 Sep 2024 @ 17517h 17m
27 Sep 2024 @ 1034 ie1d 4h 5m
26 Sep 2024 @ 0629 ie wc15h 7m
25 Sep 2024 @ 1522 wc1d 6h 44m
24 Sep 2024 @ 083813h 38m
23 Sep 2024 @ 1900 ie wc1d 2h 18m
22 Sep 2024 @ 1642 wc5h 51m
22 Sep 2024 @ 10515h 54m
22 Sep 2024 @ 0457 wc7h 10m
21 Sep 2024 @ 2147 wc13h 38m
21 Sep 2024 @ 0809 ie20h 11m
20 Sep 2024 @ 11587h 20m
20 Sep 2024 @ 0438 ns wc7h 6m
19 Sep 2024 @ 2132 ns wc5h 11m
19 Sep 2024 @ 16216h 52m
19 Sep 2024 @ 09291d 6h 31m
18 Sep 2024 @ 0258 ns wc18h 47m
17 Sep 2024 @ 0811 ie16h 24m
16 Sep 2024 @ 1547 ie16h 10m
15 Sep 2024 @ 2337 ns wc6h 21m
15 Sep 2024 @ 1716 ie wc7h 1m
15 Sep 2024 @ 1015 ie18h 14m
14 Sep 2024 @ 1601 ns wc5h 41m
14 Sep 2024 @ 1020 ie12h 35m
13 Sep 2024 @ 2145 ie wc6h 8m
13 Sep 2024 @ 1537 ns1d 22h 15m
11 Sep 2024 @ 1722 wc6h 54m
11 Sep 2024 @ 1028 ini20h 25m
10 Sep 2024 @ 1403 ie wc>2h 11m 5h 53m
10 Sep 2024 @ 081015h 50m
09 Sep 2024 @ 16205h 28m
09 Sep 2024 @ 10522d 46m

Interval Statistics

Interval Count100
Min3h 44m
Max3d 19h 56m
Mean18h 27m
Median16h 0m

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
37759 25 Oct 2024 @ 1608 --- Lizzysa Grotto
37661 20 Oct 2024 @ 2231 --- MikeG (wc observation in poor lighting) Possibly ended an eruption a few minutes ago. If so, it was a short-mode eruption that started after dark. The daytime eruption ended ~15:20.
37634 19 Oct 2024 @ 0950 --- rwd03 Sleeping.
37603 17 Oct 2024 @ 0730 --- K.Cooper off sometimes overnight. Around 0540 per CalebD
37598 16 Oct 2024 @ 1832 --- K.Cooper Grotto still ie. 24hr+ marathon ongoing
37583 15 Oct 2024 @ 1511 --- K.Cooper quiet
37409 05 Oct 2024 @ 0752 --- Darcie Grotto shut off
37408 04 Oct 2024 @ 1749 --- Darcie Grotto off
37274 30 Sep 2024 @ 0809 --- ddshepard Quiet
37209 28 Sep 2024 @ 1415 --- User34 Shutting down. Tried to hang in there for a while but couldn't sustain
37200 28 Sep 2024 @ 0823 --- ddshepard Quit about this time
37122 23 Sep 2024 @ 0920 --- Graham Quit recently. Bijou is off, so likely a long eruption from yesterday.
37101 21 Sep 2024 @ 0913 21 Sep 2024 @ 0917 ddshepard Quiet during this time
36981 15 Sep 2024 @ 1120 --- CP Eruption ended.
36823 07 Sep 2024 @ 1153 --- SteveO End at 1153.
36793 06 Sep 2024 @ 1252 --- Kyle end of eruption
36773 05 Sep 2024 @ 1223 --- CraigC Grotto shut off
36763 05 Sep 2024 @ 0720 --- CraigC Grotto off
36757 04 Sep 2024 @ 1435 --- Dave W Grotto off. Don't know what time it stopped, but it was off when I walked by at 1435.
36736 04 Sep 2024 @ 0804 --- CraigC Grotto turned off
36717 03 Sep 2024 @ 1029 --- CraigC Grotto shut off
36709 03 Sep 2024 @ 0659 --- CraigC Grotto off Marathon pool down slightly Spa up, 1 vent on
36681 01 Sep 2024 @ 0822 --- BrianR End of eruption
36660 31 Aug 2024 @ 1427 --- BrianR End of eruption
36648 30 Aug 2024 @ 1930 --- BrianR End of eruption
36632 30 Aug 2024 @ 1435 --- BrianR End of eruption
36626 30 Aug 2024 @ 1004 --- BrianR End of eruption
36619 29 Aug 2024 @ 1817 --- BrianR End of eruption
36611 29 Aug 2024 @ 1135 --- BrianR End of eruption
36608 29 Aug 2024 @ 0738 --- BrianR End of eruption
36602 28 Aug 2024 @ 1840 --- BrianR End of eruption
36599 28 Aug 2024 @ 1435 --- BrianR End of eruption
36598 28 Aug 2024 @ 1038 --- BrianR End of eruption
36567 27 Aug 2024 @ 1310 --- BrianR End of eruption
36566 27 Aug 2024 @ 0745 --- BrianR End of eruption
36557 26 Aug 2024 @ 0827 --- BrianR End of eruption
36550 26 Aug 2024 @ 0652 --- CraigC Grotto off. Grotto Fountain splashing. Pressure pool up.
36538 24 Aug 2024 @ 1919 --- BrianR Leaving area Grotto is still in eruption
36518 23 Aug 2024 @ 1152 --- BrianR End of eruption
36481 19 Aug 2024 @ 2105 --- Craigmon99 Unattended. Too hungry and without flashlight. No eruption yet
36476 19 Aug 2024 @ 1917 --- Craigmon99 Central vents on CV very lazy 1919 Off by 1922
36465 19 Aug 2024 @ 1405 --- Tara quit around this time
36462 19 Aug 2024 @ 0714 --- Darcie Off. Marathon pool down
36421 15 Aug 2024 @ 1940 --- William End of eruption
36416 15 Aug 2024 @ 0835 15 Aug 2024 @ 0915 William Turned off during this time
36374 11 Aug 2024 @ 1739 --- Ben VL Quit in the last 10m.
36365 11 Aug 2024 @ 0820 --- CraigC just noticed that marathon pool is low
36359 11 Aug 2024 @ 0637 --- CraigC Grotto off
36351 10 Aug 2024 @ 1120 --- CraigC Grotto off
36334 09 Aug 2024 @ 1010 --- CraigC Grotto off
36321 08 Aug 2024 @ 0719 --- CraigC Grotto off
36290 05 Aug 2024 @ 1230 --- CraigC Grotto off
36134 27 Jul 2024 @ 1428 --- EmilyW Off at this time
36120 26 Jul 2024 @ 1600 --- EmilyW Off at this time. Likely earlier
36119 26 Jul 2024 @ 1538 --- Polly Grotto ie. Marathon in progress.
36121 26 Jul 2024 @ 0820 --- Borg Grotto ie at 8:20, bijou off
36098 25 Jul 2024 @ 1022 --- Polly Off sometime before 1020
36099 25 Jul 2024 @ 0715 --- EmilyW Off at this time when walking to artemisia
36086 24 Jul 2024 @ 2005 --- deanl quiet
36075 24 Jul 2024 @ 1238 --- Polly Last splash seen at 1238. Grotto off.
36052 23 Jul 2024 @ 1030 --- Polly Grotto appears to be off by this time, as seen from Oblong. There was a lot of steam there at about 1005 that may have been a Rocket, but I couldn’t see water.
36044 22 Jul 2024 @ 2150 --- Joel Off when I walked by
36033 22 Jul 2024 @ 1523 --- Polly Last splash seen at 1523. Grotto off.
36030 22 Jul 2024 @ 1034 --- deanl Grotto is really trying to start but Spa is up and may Hold It off. i don't see activity in GF yet.
36027 22 Jul 2024 @ 0916 --- Polly Grotto was quiet when I walked by
36015 21 Jul 2024 @ 1045 --- deanl ending now from an apparent marathon (Bijou is quiet)
35994 20 Jul 2024 @ 1200 --- Polly Grotto is quiet. Visitor passer-by remarked that it had been ie when they walked by on their way down the path.
35993 20 Jul 2024 @ 0730 --- deanl ending. last splash i saw 0732
35987 19 Jul 2024 @ 0922 --- Polly Grotto was already off when I went by at about 0922.
35980 19 Jul 2024 @ 0820 --- deanl Bijou looked off as I went by, so I assume Grotto is in marathon.
35946 17 Jul 2024 @ 1905 --- deanl ending after Rocket
35940 17 Jul 2024 @ 1235 --- Polly Last splash seen 1237. Grotto off. I was only here a short time so I don’t know if there was a Rocket.
35919 16 Jul 2024 @ 1427 --- Polly Last splash seen at this time. Grotto off.
35913 16 Jul 2024 @ 1011 --- Polly Quiet grumbles
35908 15 Jul 2024 @ 1600 --- deanl off by 1600
35898 15 Jul 2024 @ 0930 --- deanl When I came by at about 0930 ijou had not fully recovered
35875 13 Jul 2024 @ 1119 --- deanl off at this time, likely ended earlier
35849 11 Jul 2024 @ 1930 --- deanl off at about this time
35838 11 Jul 2024 @ 1145 --- deanl off at about 1145 after Rocket
35823 10 Jul 2024 @ 1041 --- deanl off at this time and may have stopped recently.
35801 09 Jul 2024 @ 0946 --- deanl Grotto is off and probably has been for a while. Spa is up and boiling in one vent so it may hold Grotto off enough to get Grotto fountain. I just saw boiling and grotto fountain and water in the pressure pool. At 1030 Spa down from overflow.
35779 08 Jul 2024 @ 1230 --- deanl i observed Grotto off and think this is close to the stop time
35708 04 Jul 2024 @ 0627 --- CraigC Grotto off
35702 03 Jul 2024 @ 1505 --- deanl Grotto stopping at 1505
35698 03 Jul 2024 @ 0840 --- CraigC Grotto shut off
35686 02 Jul 2024 @ 1830 --- RMichaels Grotto eruption ended around 1830.
35677 02 Jul 2024 @ 1310 --- Polly Grotto was quiet when I went by. (Already off)
35660 01 Jul 2024 @ 1350 --- deanl off at about 1350
35658 01 Jul 2024 @ 0752 --- deanl off before 0750
35640 30 Jun 2024 @ 1500 --- deanl off at about 1500
35632 30 Jun 2024 @ 0817 --- BrianR End of eruption
35628 30 Jun 2024 @ 0635 --- CraigC gf splashing, pool up but not full
35617 29 Jun 2024 @ 1442 --- BrianR End of eruption
35615 29 Jun 2024 @ 0756 --- BrianR End of eruption
35612 29 Jun 2024 @ 0710 --- BrianR End of eruption, shutdown immediately after Rocket with only one in cone splash. Totally silent
35609 29 Jun 2024 @ 0620 --- CraigC pressure pool full, gf splashing
35598 27 Jun 2024 @ 2050 --- BrianR Still i.e. from this morning
35581 26 Jun 2024 @ 1607 --- BrianR End of eruption, No Rocket (canceled due to inclement weather)
35571 26 Jun 2024 @ 1031 --- BrianR End of eruption
35560 25 Jun 2024 @ 1653 --- BrianR End of eruption
EntrySourceLinkComment
18 Aug 2020 @ 1452 JSJ https://www.youtube.com/watch?v=L4pz9gWnQwk Video by Craig Corless showing the start of Grotto Geyser's 2:52 PM-onward eruption on 18 August 2020, with both Grotto Fountain Geyser & South Grotto Fountain Geyser erupting in the background.
03 Oct 2019 @ 1526 EricZ https://www.youtube.com/watch?v=YpsAVShVyxs&feature=youtu.be Grotto Start
15 Aug 2018 @ 0941 JSJ https://www.flickr.com/photos/jsjgeology/32563168958 Photo of initial runoff (approaching Variable Spring) from Grotto Geyser's 9:41 AM-onward eruption on 15 August 2018.
15 Aug 2018 @ 0941 JSJ https://www.flickr.com/photos/jsjgeology/44618689690 Photo of Grotto Geyser's 9:41 AM-onward eruption on 15 August 2018.
14 Aug 2015 @ 1314 JSJ https://www.flickr.com/photos/jsjgeology/21145226344 Photo of Grotto Geyser's 1:14 PM-onward eruption on 14 August 2015.
08 Jul 2014 @ 1430 JSJ https://www.flickr.com/photos/jsjgeology/15106150617 Photo of Grotto Geyser erupting during the mid-afternoon of 8 July 2014.
Baseline does not exist.