Last Known Eruption
1d 10h 55m ago

Latest Eruptions

Eruption DurationCodeInterval
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
24 Mar 2025 @ 2029 ns wc---6h 50m
24 Mar 2025 @ 1339 wc12m -1Q7h 11m
24 Mar 2025 @ 0628 wc-1-13h 32m
23 Mar 2025 @ 1656 ie wc---7h 19m
23 Mar 2025 @ 0937 wc---15h 17m
22 Mar 2025 @ 1820 wc---7h 32m
22 Mar 2025 @ 1048 wc-1-2d 14h 44m
19 Mar 2025 @ 2004 wc---7h 50m
19 Mar 2025 @ 1214 wc-2-7h 5m
19 Mar 2025 @ 0509 wc-1-14h 11m
18 Mar 2025 @ 1458 wc-2-8h 54m
18 Mar 2025 @ 0604 wc---7h 20m
17 Mar 2025 @ 2244 wc---19h 18m
17 Mar 2025 @ 0326 wc---13h 32m
16 Mar 2025 @ 1354 wc---13h 38m
16 Mar 2025 @ 0016 wc---6h 56m
15 Mar 2025 @ 1720 ie wc-1-6h 27m
15 Mar 2025 @ 1053 ns wc---6h 47m
15 Mar 2025 @ 0406 wc-1-14h 15m
14 Mar 2025 @ 1351T2-7h 6m
14 Mar 2025 @ 0645 wc-1-14h 51m
13 Mar 2025 @ 1554 wc-2-5h 55m
13 Mar 2025 @ 0959 ie wc---6h 17m
13 Mar 2025 @ 0342 wc---6h 25m
12 Mar 2025 @ 2117 wc---7h 9m
12 Mar 2025 @ 1408 wc-1-6h 20m
12 Mar 2025 @ 0748 wc-1-6h 59m
12 Mar 2025 @ 0049 wc-2-14h 59m
11 Mar 2025 @ 0950 ns wc-1-7h 48m
11 Mar 2025 @ 0202 wc-1-6h 34m
10 Mar 2025 @ 1928 wc-2-6h 37m
10 Mar 2025 @ 1251 ie wc-1-6h 54m
10 Mar 2025 @ 0557 wc-2-6h 31m
09 Mar 2025 @ 2326 wc---6h 15m
09 Mar 2025 @ 1711 wc---7h 7m
09 Mar 2025 @ 1004 ie wc---8h 19m
09 Mar 2025 @ 0045 wc---6h 23m
08 Mar 2025 @ 1822---7h 52m
08 Mar 2025 @ 1030 wc-2-6h 52m
08 Mar 2025 @ 0338 wc---7h 11m
07 Mar 2025 @ 2027 wc-1-7h 17m
07 Mar 2025 @ 1310 wc---6h 25m
07 Mar 2025 @ 0645 A---7h 21m
06 Mar 2025 @ 2324 wc---6h 14m
06 Mar 2025 @ 1710 wc-1-5h 55m
06 Mar 2025 @ 1115 A---6h 0m
06 Mar 2025 @ 0515 A---6h 20m
05 Mar 2025 @ 2255 wc---7h 12m
05 Mar 2025 @ 1543 ie---6h 5m
05 Mar 2025 @ 0938 ns wc---19h 57m
04 Mar 2025 @ 1341 wc-1C6h 21m
04 Mar 2025 @ 0720 wc-1-16h 52m
03 Mar 2025 @ 1428 wc-1Q7h 2m
03 Mar 2025 @ 0726 ie wc---12h 27m
02 Mar 2025 @ 1859 ie wc-2-6h 34m
02 Mar 2025 @ 1225~11m G1Q6h 21m
02 Mar 2025 @ 0604 wc-2-13h 4m
01 Mar 2025 @ 1700 A---6h 25m
01 Mar 2025 @ 103511m 48s G1Q6h 26m
01 Mar 2025 @ 0409 wc---7h 19m
28 Feb 2025 @ 2050 A---6h 55m
28 Feb 2025 @ 1355---7h 38m
28 Feb 2025 @ 0617 wc-2-14h 45m
27 Feb 2025 @ 153211m 0s D2/G2Q6h 32m
27 Feb 2025 @ 0900 A---13h 26m
26 Feb 2025 @ 1934 wc---6h 44m
26 Feb 2025 @ 1250 ns---8h 51m
26 Feb 2025 @ 0359 wc---6h 28m
25 Feb 2025 @ 213113m 4s G2*Q7h 9m
25 Feb 2025 @ 1422~10.5m G2Q8h 7m
25 Feb 2025 @ 0615 A---6h 35m
24 Feb 2025 @ 234013m 7s D0/G1Q6h 32m
24 Feb 2025 @ 170813m 13s G1Q6h 36m
24 Feb 2025 @ 10329m 47s D0/G1C6h 9m
24 Feb 2025 @ 0423 wc---13h 52m
23 Feb 2025 @ 1431 wc---23h 31m
22 Feb 2025 @ 1500 wc---6h 39m
22 Feb 2025 @ 0821 ie wc---21h 56m
21 Feb 2025 @ 1025 ns wc---6h 52m
21 Feb 2025 @ 0333 wc---8h 0m
20 Feb 2025 @ 1933 wc---8h 26m
20 Feb 2025 @ 1107 wc~10m ---6h 20m
20 Feb 2025 @ 0447 wc-1-6h 41m
19 Feb 2025 @ 2206 wc---7h 46m
19 Feb 2025 @ 1420 wc-2-6h 32m
19 Feb 2025 @ 0748 ns wc---12h 38m
18 Feb 2025 @ 1910 wc---9h 26m
18 Feb 2025 @ 0944 ie wc-1-6h 57m
18 Feb 2025 @ 0247 wc---13h 19m
17 Feb 2025 @ 1328 wc---6h 25m
17 Feb 2025 @ 0703 ie wc-2-13h 6m
16 Feb 2025 @ 1757 wc-2-5h 53m
16 Feb 2025 @ 1204 ? ie wc---13h 26m
15 Feb 2025 @ 2238 wc---7h 4m
15 Feb 2025 @ 1534 wc---9h 18m
15 Feb 2025 @ 0616 wc-2-6h 54m

Interval Statistics

Interval Count100
Min5h 53m
Max2d 14h 44m
Mean9h 31m
Median7h 8m
Grand-Specific
Start8G/1T (88.89% G)
Max Bursts2
Mean Bursts1.43
Median Bursts1
End9Q/4C (69.23% 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