Last Known Eruption
5h 44m ago
Predicted Next Eruption
Today at 0222 ± 105 minutes

Latest Eruptions

Eruption DurationCodeInterval
14 Jun 2025 @ 1837:2510m 15s G2Q8h 55m
14 Jun 2025 @ 0942 ie10-11 minutes-1Q8h 9m
14 Jun 2025 @ 013311m 15s T1Q8h 2m
13 Jun 2025 @ 173110m 21s T1Q8h 5m
13 Jun 2025 @ 092610m 6s D6/T1C8h 25m
13 Jun 2025 @ 0101T1C8h 9m
12 Jun 2025 @ 16529m 32s T1C7h 41m
12 Jun 2025 @ 09119m 1s D7/T1C8h 32m
12 Jun 2025 @ 00399m ---8h 28m
11 Jun 2025 @ 16119m 29s T1C7h 34m
11 Jun 2025 @ 0837:0012m 24s D3/T2*Q12h 18m
10 Jun 2025 @ 201910m 19s D0/G1C7h 12m
10 Jun 2025 @ 130711m 5s D3D0/T1Q7h 29m
10 Jun 2025 @ 0538 wc-1-9h 4m
09 Jun 2025 @ 2033:4510m 22s G1Q6h 36m 44s
09 Jun 2025 @ 1357:0110m 1s D3/D5/G2Q8h 45m
09 Jun 2025 @ 0512 ns wc-1-6h 21m
08 Jun 2025 @ 225111m 1s T1Q7h 44m
08 Jun 2025 @ 15079m 59s D6/T1C8h 0m
08 Jun 2025 @ 07079m 55s T1C9h 26m
07 Jun 2025 @ 214111m 19s G1Q7h 28m
07 Jun 2025 @ 141310m 10s T2Q7h 46m
07 Jun 2025 @ 0627 wc-1-8h 20m
06 Jun 2025 @ 220710m 23s G2Q7h 57m
06 Jun 2025 @ 141010m 19s G1Q6h 47m
06 Jun 2025 @ 072311m 16s G1Q7h 2m
06 Jun 2025 @ 002110m 25s T1Q9h 50m
05 Jun 2025 @ 143110m 46s G1Q6h 40m
05 Jun 2025 @ 075111m 14s T2Q8h 46m
04 Jun 2025 @ 23058m 40s G1C6h 44m
04 Jun 2025 @ 162111m 18s G1Q8h 44m
04 Jun 2025 @ 07379m 40s D2/G2Q14h 38m
03 Jun 2025 @ 16599m 45s D0/T1C7h 24m
03 Jun 2025 @ 09359m 1s T2C7h 56m
03 Jun 2025 @ 0139G1C7h 40m
02 Jun 2025 @ 17599m 10s G1C6h 44m
02 Jun 2025 @ 111511m 4s G1Q6h 58m
02 Jun 2025 @ 0417 wc-2-8h 15m
01 Jun 2025 @ 200210m 13s D2/G1C7h 16m
01 Jun 2025 @ 12469m 38s D7/T1C8h 53m
01 Jun 2025 @ 0353 wc-2-6h 44m
31 May 2025 @ 210911m 34s D6/T2*Q8h 16m
31 May 2025 @ 125310m 46s G1Q6h 30m
31 May 2025 @ 062312m 1s G1Q6h 33m
30 May 2025 @ 23509m 31s D5/G1Q7h 47m
30 May 2025 @ 16039m 39s G1C7h 5m
30 May 2025 @ 08588m 30s D0/T1C7h 22m
30 May 2025 @ 013610m 20s G1C8h 0m
29 May 2025 @ 17369m 44s G1C8h 2m
29 May 2025 @ 09349m 49s D7/G1C8h 45m
29 May 2025 @ 004911m 22s G1Q6h 50m
28 May 2025 @ 175911m 26s G1Q6h 51m
28 May 2025 @ 110811m 51s D4/G1Q6h 51m
28 May 2025 @ 0417 ie wc---6h 54m
27 May 2025 @ 2123 wc-2-5h 53m
27 May 2025 @ 153010m 12s G2C7h 44m
27 May 2025 @ 074611m 4s D4/T2*Q10h 5m
26 May 2025 @ 214111m T1Q8h 31m
26 May 2025 @ 131010m 12s G2*Q6h 58m
26 May 2025 @ 0612 wc-2-8h 26m
25 May 2025 @ 2146 wc---7h 29m
25 May 2025 @ 141710m 50s G1Q6h 58m
25 May 2025 @ 071912m 53s D3D0/G2*Q13h 21m
24 May 2025 @ 17589m 52s G1C6h 12m
24 May 2025 @ 114610m 13s G2C6h 44m
24 May 2025 @ 0502 wc-1-8h 9m
23 May 2025 @ 205310m 28s T1C7h 52m
23 May 2025 @ 13019m 35s V7/T1Q8h 37m
23 May 2025 @ 0424 wc-1-6h 44m
22 May 2025 @ 21409m 49s D7/G1C9h 26m
22 May 2025 @ 121411m 40s T1Q6h 47m
22 May 2025 @ 0527 wc-1-6h 32m
21 May 2025 @ 2255 ie---6h 54m
21 May 2025 @ 160111m 7s G2Q6h 39m
21 May 2025 @ 0922 wc-1-6h 37m
21 May 2025 @ 0245 A---6h 34m
20 May 2025 @ 2011 ie12m ---6h 35m
20 May 2025 @ 1336 wc-2-7h 13m
20 May 2025 @ 0623 wc-1-16h 4m
19 May 2025 @ 1419~11m G2Q6h 39m
19 May 2025 @ 0740~10m G1C14h 52m
18 May 2025 @ 1648~11m G1Q6h 42m
18 May 2025 @ 100612m 32s G2Q19h 14m
17 May 2025 @ 145210m 44s D7/T1C8h 15m
17 May 2025 @ 0637 wc-1-14h 1m
16 May 2025 @ 163611m 0s D2/G1Q8h 1m
16 May 2025 @ 08359m 30s G2Q9h 39m
15 May 2025 @ 2256~10m D0/T1Q6h 36m
15 May 2025 @ 162011m 9s G1Q6h 41m
15 May 2025 @ 09399m 45s G1C7h 9m
15 May 2025 @ 0230 A---6h 34m
14 May 2025 @ 1956T2Q7h 11m
14 May 2025 @ 124511m 0s G2Q6h 23m
14 May 2025 @ 0622 wc-1-6h 36m
13 May 2025 @ 2346 wc---6h 22m
13 May 2025 @ 1724-2-6h 59m
13 May 2025 @ 1025 ns-2-6h 19m
13 May 2025 @ 0406 wc-1-7h 48m
12 May 2025 @ 2018-1-5h 56m
12 May 2025 @ 142211m 40s G1Q6h 34m

Interval Statistics

Interval Count100
Min5h 53m
Max19h 14m
Mean8h 1m
Median7h 29m
Grand-Specific
Start45G/29T (60.81% G)
Max Bursts2
Mean Bursts1.3
Median Bursts1
End45Q/30C (60% Q)

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
39600 01 Jun 2025 @ 0502 --- SteveO Grand's pool empty, Turban & Vent quiet.
39418 28 May 2025 @ 0508 --- SteveO Grand's pool is empty, Turban and Vent erupting
39084 16 May 2025 @ 0800 --- K.Cooper In ovfl
38221 27 Jan 2025 @ 0900 --- ghost842 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 geyserG0bLiN 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
EntrySourceLinkComment
27 May 2025 @ 2123 Joe   https://youtu.be/xZzoLcu6NDY grand video
22 May 2025 @ 0527 Joe   https://youtu.be/6wSXShfJ0s8 Grand Aurum video
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.
BaselineDistance (ft)Description
South Side 200Jugwalk south of Grand at the Y junction at Belgian Pool