Last Known Eruption
22m ago
Predicted Next Eruption
May 01 at 0215 ± 105 minutes

Latest Eruptions

Eruption DurationCodeInterval
30 Apr 2025 @ 183011m 33s ---6h 8m
30 Apr 2025 @ 122210m 14s G1C6h 37m
30 Apr 2025 @ 0545 A---13h 56m
29 Apr 2025 @ 1549~11m G2Q6h 27m
29 Apr 2025 @ 0922 wc-2-14h 0m
28 Apr 2025 @ 192211m 16s G2Q6h 56m
28 Apr 2025 @ 122610m 55s D6/G2Q8h 11m
28 Apr 2025 @ 0415 A---13h 21m
27 Apr 2025 @ 1454G2Q7h 14m
27 Apr 2025 @ 0740 ns-2Q12h 17m
26 Apr 2025 @ 1923G2Q7h 10m
26 Apr 2025 @ 1213~8m 30s D5/G1C7h 28m
26 Apr 2025 @ 0445 A---7h 20m
25 Apr 2025 @ 2125 wc-2-6h 47m
25 Apr 2025 @ 143810m G1C6h 38m
25 Apr 2025 @ 0800 A---14h 41m
24 Apr 2025 @ 1719 wc-2-6h 22m
24 Apr 2025 @ 105710m T1C7h 12m
24 Apr 2025 @ 0345 A---8h 58m
23 Apr 2025 @ 184710m 38s G2Q6h 24m
23 Apr 2025 @ 122310m 37s G1C6h 32m
23 Apr 2025 @ 0551 wc-1-13h 0m
22 Apr 2025 @ 1651 wc---6h 22m
22 Apr 2025 @ 102911m 19s G2Q8h 29m
22 Apr 2025 @ 0200 A---6h 31m
21 Apr 2025 @ 1929 ns wc-1-6h 33m
21 Apr 2025 @ 1256 ie---7h 4m
21 Apr 2025 @ 0552 wc-1-12h 38m
20 Apr 2025 @ 171410m G1C6h 18m
20 Apr 2025 @ 10568m 52s G1C7h 11m
20 Apr 2025 @ 0345 A---14h 5m
19 Apr 2025 @ 1340---6h 17m
19 Apr 2025 @ 0723 wc---13h 42m
18 Apr 2025 @ 174110m 42s G1Q6h 33m
18 Apr 2025 @ 110811m 12s D2/T1Q7h 16m
18 Apr 2025 @ 0352 wc-1-7h 7m
17 Apr 2025 @ 2045 wc-1-19h 14m
17 Apr 2025 @ 0131 wc---7h 23m
16 Apr 2025 @ 1808 wc---7h 41m
16 Apr 2025 @ 1027 wc-1Q9h 4m
16 Apr 2025 @ 0123 wc-2-7h 48m
15 Apr 2025 @ 1735-2-7h 42m
15 Apr 2025 @ 0953 wc-1-6h 44m
15 Apr 2025 @ 0309 wc-1-6h 24m
14 Apr 2025 @ 2045 wc-1-8h 44m
14 Apr 2025 @ 1201 ie wc---7h 5m
14 Apr 2025 @ 0456 wc-1-7h 3m
13 Apr 2025 @ 2153 wc---6h 19m
13 Apr 2025 @ 1534 ie wc---7h 12m
13 Apr 2025 @ 0822 ie wc---7h 31m
13 Apr 2025 @ 0051 wc---6h 54m
12 Apr 2025 @ 1757 wc-1-6h 27m
12 Apr 2025 @ 1130 ie wc---6h 8m
12 Apr 2025 @ 0522 wc-1-6h 4m
11 Apr 2025 @ 2318 wc-1-8h 8m
11 Apr 2025 @ 1510 ns wc---6h 22m
11 Apr 2025 @ 0848-1Q6h 38m
11 Apr 2025 @ 0210 wc-2-7h 15m
10 Apr 2025 @ 1855 wc-1-7h 22m
10 Apr 2025 @ 1133 wc10m -1-7h 0m
10 Apr 2025 @ 0433 wc-1-6h 20m
09 Apr 2025 @ 2213 wc-2-7h 55m
09 Apr 2025 @ 1418 wc-1-6h 51m
09 Apr 2025 @ 0727 wc-2-6h 53m
09 Apr 2025 @ 0034 wc-1-13h 46m
08 Apr 2025 @ 1048 wc-1-7h 32m
08 Apr 2025 @ 0316 wc-1-7h 2m
07 Apr 2025 @ 2014 wc-1-6h 9m
07 Apr 2025 @ 1405 wc-2-7h 55m
07 Apr 2025 @ 0610 wc-3-7h 44m
06 Apr 2025 @ 2226 wc---6h 26m
06 Apr 2025 @ 1600 wc-1-7h 6m
06 Apr 2025 @ 0854 ie wc-1-6h 31m
06 Apr 2025 @ 0223 wc-2-6h 47m
05 Apr 2025 @ 1936 wc-1-6h 24m
05 Apr 2025 @ 1312 wc---7h 21m
05 Apr 2025 @ 0551 wc---7h 9m
04 Apr 2025 @ 2242 wc-1-7h 58m
04 Apr 2025 @ 1444 wc---8h 10m
04 Apr 2025 @ 0634 wc-1-7h 36m
03 Apr 2025 @ 2258 wc---6h 51m
03 Apr 2025 @ 1607 wc-2-6h 40m
03 Apr 2025 @ 0927 ns-2-14h 27m
02 Apr 2025 @ 1900 wc---7h 43m
02 Apr 2025 @ 1117 wc-2-12h 39m
01 Apr 2025 @ 2238 wc---6h 46m
01 Apr 2025 @ 1552 ie wc---6h 18m
01 Apr 2025 @ 0934 ie wc-1-21h 36m
31 Mar 2025 @ 1158 ie wc---7h 2m
31 Mar 2025 @ 0456 wc---13h 48m
30 Mar 2025 @ 1508 ie wc---6h 31m
30 Mar 2025 @ 0837 wc---13h 28m
29 Mar 2025 @ 1909 ie wc---7h 39m
29 Mar 2025 @ 1130 ns wc---20h 54m
28 Mar 2025 @ 1436 ns wc---6h 26m
28 Mar 2025 @ 0810 wc-1Q1d 15h 17m
26 Mar 2025 @ 1653 wc-1-7h 26m
26 Mar 2025 @ 0927 ie wc-2-13h 55m
25 Mar 2025 @ 1932 wc9m -1C6h 31m
25 Mar 2025 @ 1301 ns wc---16h 32m

Interval Statistics

Interval Count100
Min6h 4m
Max1d 15h 17m
Mean8h 51m
Median7h 11m
Grand-Specific
Start14G/2T (87.5% G)
Max Bursts3
Mean Bursts1.38
Median Bursts1
End14Q/8C (63.64% Q)

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
38221 27 Jan 2025 @ 0900 --- BrandonC Water in pool but don’t know if there was overflow. Staying for a cycle to see if there will be runoff
38157 06 Jan 2025 @ 0741 --- Graham In overflow. I'm not sure for how long.
38049 21 Dec 2024 @ 0708 --- mhreed Alternating between quiet and sloshing lazily in crater. It’ll be a few hours.
37624 18 Oct 2024 @ 0802 18 Oct 2024 @ 0812 bellamattio sudden tall start. ended abruptly. TALL ENCORE :D boardwalk very slippery be careful<3
37616 17 Oct 2024 @ 1703 --- kyle.G grand erupted sometime before 16:55. near end when I arrived
37469 10 Oct 2024 @ 0827 --- Ben VL No eruption yet.
37431 07 Oct 2024 @ 1147 --- Betty In overflow
37392 04 Oct 2024 @ 0800 --- Graham In "normal" overflow. No idea of the start time.
37337 03 Oct 2024 @ 0700 --- Graham Empty. Likely before 0600 per visitors.
37328 02 Oct 2024 @ 0840 --- Graham Close to overflow
37307 01 Oct 2024 @ 1031 --- Lizzysa An encore!
37300 01 Oct 2024 @ 0835 --- Ben VL No grand yet. (Hopefully not the same one I abandoned last night)
37199 28 Sep 2024 @ 0749 --- ddshepard Quiet; empty.
37160 26 Sep 2024 @ 0732 --- ddshepard Empty; Turban splashing
37148 25 Sep 2024 @ 0900 --- TSBryan Grand was late i.e. at 0900
36732 04 Sep 2024 @ 0643 --- SteveO Pool is empty, Turban and Vent quiet.
36711 03 Sep 2024 @ 0743 --- Graham In overflow under the boardwalk. Not first overflow.
36710 03 Sep 2024 @ 0710 --- Scott H no overflow
36654 31 Aug 2024 @ 0749 --- Graham Grand almost full with 0703 Turban. 0720, 0737 Turban. 0749 in overflow. Likely missed first overflow on one of prior cycles. Sorry, not used to watching for overflow.
36647 30 Aug 2024 @ 1905 --- ge now in delay 0
36430 17 Aug 2024 @ 0656 --- JimS No eruption yet
36397 14 Aug 2024 @ 0707 --- JimS Already in overflow
36387 13 Aug 2024 @ 0643 --- JimS Pool empty, Turban and Vent quiet. Pool still steaming. Grand erupted a short time ago.
36362 11 Aug 2024 @ 0658 --- JimS Already in overflow
36345 10 Aug 2024 @ 0825 --- JimS Start of overflow
36344 10 Aug 2024 @ 0656 --- JimS Pool nearly empty, Turban i.e
36282 05 Aug 2024 @ 0640 --- JimS Already in overflow
36258 04 Aug 2024 @ 0709 --- JimS First water into the pool.
36256 04 Aug 2024 @ 0630 --- JimS Pool empty, Turban and Vent quiet.
36240 03 Aug 2024 @ 0624 --- JimS Already in overflow
36219 02 Aug 2024 @ 0720 --- JimS Start of overflow
36200 01 Aug 2024 @ 0836 --- mhreed Has already hit overflow
36196 01 Aug 2024 @ 0635 --- JimS Not yet in overflow
36187 31 Jul 2024 @ 0631 --- JimS Already in overflow
36138 27 Jul 2024 @ 1615 --- mdschwarz Couple of 1-foot surges + high-pool waves
35887 14 Jul 2024 @ 0615 --- JimS First overflow
35884 14 Jul 2024 @ 0610 --- JimS Appears not quite in overflow
35867 13 Jul 2024 @ 0600 --- JimS Pool empty, Turban and Vent quiet.
35858 12 Jul 2024 @ 0651 --- JimS First water into pool
35857 12 Jul 2024 @ 0616 --- JimS Pool empty, Turban and Vent quiet.
35834 11 Jul 2024 @ 0643 --- JimS First water into pool.
35831 11 Jul 2024 @ 0546 --- JimS Pool empty, Vent and Turban i.e
35798 09 Jul 2024 @ 0710 --- JimS First overflow from pool
35796 09 Jul 2024 @ 0615 --- JimS Pool has some water, Turban i.e, Vent quiet
35736 06 Jul 2024 @ 0556 --- JimS Already in overflow
35694 03 Jul 2024 @ 0600 --- JimS Already in overflow
35671 02 Jul 2024 @ 0600 --- JimS Already in overflow
35625 30 Jun 2024 @ 0615 --- JimS In overflow
35583 27 Jun 2024 @ 0619 --- JimS First water into the pool.
35565 26 Jun 2024 @ 0555 --- JimS Already in overflow
35469 23 Jun 2024 @ 0603 --- JimS Pool nearly empty. Turban and Vent quiet.
35437 22 Jun 2024 @ 0607 --- JimS Pool empty, Vent and Turban ie.
35317 18 Jun 2024 @ 1919 --- Forestbewithyou 2 big boops/false starts
35270 17 Jun 2024 @ 0633 --- JimS First water into the pool
35269 17 Jun 2024 @ 0608 --- JimS Post eruptive. Vent and Turban quiet. Pool appears totally empty.
35241 16 Jun 2024 @ 0621 --- JimS Post eruptive, Vent quiet, Turban i.e., some water in the pool.
35231 15 Jun 2024 @ 0746 --- JimS First overflow from pool
35229 15 Jun 2024 @ 0616 --- JimS Post eruptive. Turban and Vent quiet.
35022 09 Jun 2024 @ 0500 --- K.Cooper a bit below half full, Mike said empty at 0300
34955 07 Jun 2024 @ 0708 --- JimS First overflow from pool
34952 07 Jun 2024 @ 0559 --- JimS Post eruptive. Already some water in the pool
34917 06 Jun 2024 @ 0617 --- JimS First water into pool at this time.
34665 25 May 2024 @ 0645 --- RLJones in eruption
34641 23 May 2024 @ 0022 --- JarnoO Either eruptive or post-eruptive at this time. In any case copious steaming until about 0100.
34185 14 Apr 2024 @ 1058 --- mhreed Water dropped back into crater mouth w/ Turban start. Has been periodically boiling.
33890 20 Jan 2024 @ 0711 --- K.Cooper empty
33879 19 Jan 2024 @ 0816 --- K.Cooper water is there, but low
33867 18 Jan 2024 @ 0745 --- K.Cooper pool decently high and overflowing
33796 15 Jan 2024 @ 0815 --- K.Cooper a few inches below overflow
33737 03 Jan 2024 @ 1105 --- mhvogel Grand erupted early this morning not too long before the post with question mark attached.
33371 22 Dec 2023 @ 1435 --- Pholli pool completely empty
33368 22 Dec 2023 @ 1005 --- aferrara pool low, no eruption since last night's as of this time. Economic in heavy overflow
28939 21 Oct 2023 @ 0731 --- User34 Nearing first overflow
28601 01 Oct 2023 @ 0709 --- NihonRanger Pool is nice and full, doing a good amount of overflow. Small ripple waves, nothing big yet.
28509 27 Sep 2023 @ 1103 --- Brian Rift off
28138 09 Sep 2023 @ 0905 --- SteveO Reached overflow.
28128 09 Sep 2023 @ 0636 --- K.Cooper Pool empty
28075 07 Sep 2023 @ 0627 --- SteveO Not in overflow yet.
28026 05 Sep 2023 @ 0757 --- JimS First overflow from pool
27800 27 Aug 2023 @ 0644 --- JimS Pool still below overflow
27770 25 Aug 2023 @ 0652 --- JimS Slight amount of water in pool. Vent and Turban quiet
27696 20 Aug 2023 @ 0622 --- JimS Already in overflow
27679 19 Aug 2023 @ 0610 --- JimS Already in overflow
27651 17 Aug 2023 @ 0627 --- JimS Already in overflow
27514 11 Aug 2023 @ 0603 --- JimS Pool empty, Turban ie, Vent quiet
27501 10 Aug 2023 @ 1622 --- minissa Some interesting afterbhrst activity started around 1610. Vigorous Vent and Turban, Grand erupting from empty pool intermittently to as high as 12 feet. Eruption was recorded as a Q, so this caught our attention. Noticed from over by Spasmodic.
27485 10 Aug 2023 @ 0619 --- JimS Already in overflow
27469 09 Aug 2023 @ 0609 --- JimS Pool below overflow
27450 07 Aug 2023 @ 0626 --- JimS Pool empty, Turban and Vent quiet
27395 03 Aug 2023 @ 0610 --- JimS Pool empty, Turban and Vent quiet
27343 30 Jul 2023 @ 1828 --- RVD Grand intermittently "erupting" from an empty pool, with some spritzy bursts matching the height of Vent Geyser which continues to go strong. Turban continues to also have strong eruptions and the Triplet has joined in. I have not seen this before. This is roughly half an hour after the main eruption (which i did not see). Stayed at Grand for almost 10 minutes to watch.
27273 28 Jul 2023 @ 0533 --- JimS Pool empty, Turban and Vent ie
27249 27 Jul 2023 @ 0611 --- JimS Already in overflow
27208 25 Jul 2023 @ 0609 --- JimS Already in overflow
27189 24 Jul 2023 @ 0608 --- JimS Already in overflow
27137 21 Jul 2023 @ 0617 --- JimS Already in overflow
27129 20 Jul 2023 @ 0602 --- JimS Pool empty, Turban and Vent quiet
27080 16 Jul 2023 @ 0553 --- JimS Pool empty, Turban and Vent quiet
27060 14 Jul 2023 @ 0508 --- dandersen Pool Empty
27043 13 Jul 2023 @ 0540 --- JimS Pool empty, Turban and Vent quiet
EntrySourceLinkComment
20 Apr 2024 @ 2224 Joe   https://youtu.be/vIlPujViDqI 4 burst Grand
10 Jul 1995 @ 1319 mhreed https://www.youtube.com/watch?v=R7Ie05P2Sgc David Schwarz video of this eruption.
07 Jan 2023 @ 1613 Delta4Heavy85 https://adobe.ly/3GsvpVV Grand's eruption from the webcams view.
04 Jan 2023 @ 1237 Delta4Heavy85 https://adobe.ly/3jZ7UfI Video of eruption from the Webcam's view
25 Nov 2022 @ 2318 Art-P https://www.youtube.com/watch?v=Q0hVAQ7RK54 GRAND video
17 May 2021 @ 0059 JoeN https://i.imgur.com/ZgC53Oh.png Grand 0059
04 Aug 2020 @ 1933 JSJ https://www.youtube.com/watch?v=wOTjWdGdOEY Video compilation showing Grand Geyser's 7:33 to 7:43 PM eruption on 4 August 2020.
06 Aug 2020 @ 1442 JSJ https://www.flickr.com/photos/jsjgeology/50213109327 Photo (out of 4) of Grand Geyser's 2:42 to 2:52 PM eruption on 6 August 2020.
25 Jul 2020 @ 1132 JSJ https://www.youtube.com/watch?v=cF1okeFGEbU Video of eruption.
02 May 2020 @ 2056 JoeN https://youtu.be/9bkNZP7Op8w 3 burst Grand
04 Apr 2020 @ 0934 JoeN https://youtu.be/-8WXc68IOd8 grand video
17 Mar 2020 @ 0915 ltgangi https://youtu.be/-yHg1pz44AY grand 03/17/2010
28 Feb 2020 @ 1219 JarnoO https://www.youtube.com/watch?v=gFsg-peggKo The video of this eruption.
18 Feb 2020 @ 1157 JarnoO https://www.youtube.com/watch?v=swxz4PHVB8w The eruption as seen from the webcam.
07 Jun 2018 @ 0713 JSJ https://www.flickr.com/photos/jsjgeology/41267057880 Photo (out of 3) of Grand Geyser's 7:13 to 7:25 AM eruption on 7 June 2018.
31 Jul 2017 @ 1608 JSJ https://www.youtube.com/watch?v=PVKlUye_S8A Time lapse video of Grand Geyser's afternoon eruption on 31 July 2017.
31 Jul 2017 @ 1608 JSJ https://www.flickr.com/photos/jsjgeology/35790098193 Photo (out of 6) of Grand Geyser's 4:08 to 4:20 PM eruption on 31 July 2017.
08 Jun 2016 @ 1409 JSJ https://www.flickr.com/photos/jsjgeology/31182392056 Thermal image (1 of 8) of Grand Geyser's 2:09 to 2:20 PM eruption on 8 June 2016.
08 Jun 2016 @ 1409 JSJ https://www.flickr.com/photos/jsjgeology/31182537916 Photo (1 of 12) of Grand Geyser's 2:09 to 2:20 PM eruption on 8 June 2016.
11 Aug 2016 @ 1454 JSJ https://www.flickr.com/photos/jsjgeology/29895281572 Photo (1 of 12) of Grand Geyser's 2:54 to 3:06 PM eruption on 11 August 2016.
BaselineDistance (ft)Description
South Side 200Jugwalk south of Grand at the Y junction at Belgian Pool