Last Known Eruption
9h 42m ago
Predicted Next Eruption
Today at 2051 ± 120 minutes

Latest Eruptions

Eruption DurationInterval
05 Aug 2020 @ 093611h 10m
04 Aug 2020 @ 2226 E10h 59m
04 Aug 2020 @ 112711h 11m
04 Aug 2020 @ 0016 E11h 0m
03 Aug 2020 @ 131611h 15m
03 Aug 2020 @ 0201 E10h 15m
02 Aug 2020 @ 154610h 42m
02 Aug 2020 @ 050411h 11m
01 Aug 2020 @ 175310h 12m
01 Aug 2020 @ 074111h 27m
31 Jul 2020 @ 201410h 29m
31 Jul 2020 @ 094512h 20m
30 Jul 2020 @ 212513h 5m
30 Jul 2020 @ 0820 E11h 33m
29 Jul 2020 @ 2047 E10h 15m
29 Jul 2020 @ 103210h 22m
29 Jul 2020 @ 0010 E10h 52m
28 Jul 2020 @ 131810h 7m
28 Jul 2020 @ 0311 E10h 59m
27 Jul 2020 @ 161211h 45m
27 Jul 2020 @ 042711h 23m
26 Jul 2020 @ 170410h 25m
26 Jul 2020 @ 063914h 14m
25 Jul 2020 @ 162510h 21m
25 Jul 2020 @ 060412h 38m
24 Jul 2020 @ 172611h 35m
24 Jul 2020 @ 05519h 35m
23 Jul 2020 @ 201615h 5m
23 Jul 2020 @ 051110h 9m
22 Jul 2020 @ 190212h 44m
22 Jul 2020 @ 061813h 34m
21 Jul 2020 @ 16449h 34m
21 Jul 2020 @ 071011h 22m
20 Jul 2020 @ 194811h 2m
20 Jul 2020 @ 084613h 37m
19 Jul 2020 @ 190912h 49m
19 Jul 2020 @ 0620 E10h 7m
18 Jul 2020 @ 2013 E10h 18m
18 Jul 2020 @ 0955 E12h 35m
17 Jul 2020 @ 212013h 46m
17 Jul 2020 @ 073414h 36m
16 Jul 2020 @ 165811h 43m
16 Jul 2020 @ 0515 ie11h 1m
15 Jul 2020 @ 181412h 8m
15 Jul 2020 @ 060611h 35m
14 Jul 2020 @ 183111h 19m
14 Jul 2020 @ 071210h 42m
13 Jul 2020 @ 2030 ie17h 9m
13 Jul 2020 @ 0321 E10h 38m
12 Jul 2020 @ 164310h 59m
12 Jul 2020 @ 0544 E10h 22m
11 Jul 2020 @ 192211h 35m
11 Jul 2020 @ 074721h 10m
10 Jul 2020 @ 10372h 27m 10h 41m
09 Jul 2020 @ 2356 E14h 11m
09 Jul 2020 @ 094511h 5m
08 Jul 2020 @ 2240 E11h 19m
08 Jul 2020 @ 112111h 30m
07 Jul 2020 @ 2351 E10h 28m
07 Jul 2020 @ 132312h 3m
07 Jul 2020 @ 0120 E10h 22m
06 Jul 2020 @ 14589h 10m
06 Jul 2020 @ 054812h 51m
05 Jul 2020 @ 16578h 53m
05 Jul 2020 @ 080412h 4m
04 Jul 2020 @ 200012h 52m
04 Jul 2020 @ 070810h 53m
03 Jul 2020 @ 201510h 50m
03 Jul 2020 @ 092511h 1m
02 Jul 2020 @ 2224 E11h 28m
02 Jul 2020 @ 105611h 1m
01 Jul 2020 @ 2355 E11h 23m
01 Jul 2020 @ 123210h 15m
01 Jul 2020 @ 0217 E11h 2m
30 Jun 2020 @ 151511h 44m
30 Jun 2020 @ 0331 E11h 41m
29 Jun 2020 @ 155022h 42m
28 Jun 2020 @ 1708 E10h 32m
28 Jun 2020 @ 063612h 31m
27 Jun 2020 @ 180511h 41m
27 Jun 2020 @ 062411h 14m
26 Jun 2020 @ 191012h 58m
26 Jun 2020 @ 061211h 50m
25 Jun 2020 @ 182216h 8m
25 Jun 2020 @ 0214 E11h 16m
24 Jun 2020 @ 145813h 20m
24 Jun 2020 @ 0138 E12h 1m
23 Jun 2020 @ 133710h 48m
23 Jun 2020 @ 0249 E11h 40m
22 Jun 2020 @ 150911h 38m
22 Jun 2020 @ 0331 E12h 58m
21 Jun 2020 @ 14339h 37m
21 Jun 2020 @ 0456 E9h 37m
20 Jun 2020 @ 1919 E12h 18m
20 Jun 2020 @ 070112h 2m
19 Jun 2020 @ 185914h 2m
19 Jun 2020 @ 0457 E12h 2m
18 Jun 2020 @ 1655 E11h 2m
18 Jun 2020 @ 055310h 58m
17 Jun 2020 @ 1855 E12h 57m

Interval Statistics

Interval Count100
Min8h 53m
Max22h 42m
Mean11h 47m
Median11h 20m

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
15151 02 Aug 2020 @ 1405 --- aferrara Nearly in overflow at 1330, water level more than 1ft below overflow when I returned at 1405
15110 26 Jul 2020 @ 1545 --- CraigC in overflow per observer
15070 21 Jul 2020 @ 1525 --- CraigC in overflow per Byron
15061 21 Jul 2020 @ 0627 --- CraigC already in overflow
15058 20 Jul 2020 @ 1822 --- William 1st overflow
15043 20 Jul 2020 @ 0650 --- CraigC 650 pool crashed, 718 in overflow
15040 19 Jul 2020 @ 1909 --- CraigC 2nd 1927 to 1932. 3rd 1941 to 1947. 4th 1956 to 2002. 5th 2009 to 2017
15039 19 Jul 2020 @ 1753 --- CraigC started overflow
14986 14 Jul 2020 @ 1715 --- CraigC already in overflow when I arrived
14965 13 Jul 2020 @ 0524 13 Jul 2020 @ 0602 LynnS From 0524 until about 0600 Great Fountain was in the post-eruptive state where it periodically splashedup water without ejecting water from the crater (coning activity that does not reflect expenditure of energy and is not included in calculations of duration based prediction models), but had not quite entered the post-eruptive state where the pool fills to a few inches below overflow, then boils for awhile (stage 1 of Tomas Vachuda’s quiet period.) About 0600 the coning started to turn to activity that looked more like boiling around the edges of and the pool level, although several inches below the rim, was visible (stage 1 of Vachuda’s quiet period).
14894 06 Jul 2020 @ 1350 --- CraigC in overflow
14889 05 Jul 2020 @ 1545 --- LynnS Already in overflow.
14879 04 Jul 2020 @ 1845 --- CraigC in overflow
14813 30 Jun 2020 @ 1305 --- User34 Seemed very close to overflow, or in early overflow
14724 24 Jun 2020 @ 1350 --- William 1st overflow
14695 20 Jun 2020 @ 0549 --- LynnS Great Fountain in very early overflow; water has not yet started trickling off the first terrace.
14657 17 Jun 2020 @ 1705 --- LynnS Not yet in overflow
14638 14 Jun 2020 @ 1542 --- aferrara Fairly high water level ~1530 dropped ~1' below overflow
14634 13 Jun 2020 @ 1645 --- William arrived to overflow with light circular boil.
14605 11 Jun 2020 @ 1957 --- William first overflow
14546 05 Jun 2020 @ 1250 --- RLJones no eruption yet as of 1250
14530 03 Jun 2020 @ 2230 --- William Still no overflow at 22:30
14236 25 May 2020 @ 1523 --- mhvogel Hey geyser enthusiasts. I went to Firehole Lake Drive this morning to retrieve the data logger eruptions times of Great Fountain. It stopped logging on April 28 so there is nearly a month of eruptions that is lost. I reconfigured the logger so as of 0940 it began logging again. I'll input the eruption times as soon as I can as it takes a long time to enter over a month's worth of data. This summer Old Faithful Park Rangers will not be predicting Great Fountain geyser. We will not be there every morning like we used to be and that's rather unfortunate. This is due to low staffing levels and operational needs. It is way beyond my control.
13952 16 Oct 2019 @ 1546 --- Maureen Firehole Lake Drive has been closed since the whole park shut down last week and has NOT reopened.
13951 16 Oct 2019 @ 1438 --- mhvogel After arduously reviewing the GF electronic data, it appears GF is going into a "wild phase". On 10/9 it was doing these small eruptions every from 0443-1622 every 20-30 minutes. On 10/10 more small eruptions every 20-30 minutes. On 10/11 and 10/12 not much of anything. On 10/13 and 10/14 GF began to have small eruptions again about every 30-60 minutes. I hope this helps.
13991 14 Oct 2019 @ 1234 --- mhvogel After reviewing the great fountain graph, the wild phase period started on 10/9 and ended on the morning/afternoon of 10/14.
13990 14 Oct 2019 @ 1224 --- mhvogel The geology department emailed me the Great Fountain electronic graph for 10/14-10/18.
13901 07 Oct 2019 @ 1042 --- underarockphoto In full overflow
13894 06 Oct 2019 @ 1120 --- cb overflow just starting on the 2nd tier.
13873 04 Oct 2019 @ 1450 --- Maureen Overflow start.
13861 04 Oct 2019 @ 0730 --- underarockphoto Five inches below overflow.
13834 30 Sep 2019 @ 1247 --- Maureen The next eruption will be after 1500.
13802 25 Sep 2019 @ 1219 --- Maureen Overflow start.
13750 19 Sep 2019 @ 0815 --- Barbara Lasseter Heavy noisy boiling in crater sometimes reaching top of crater. Runoff channels holding water
13715 16 Sep 2019 @ 0835 --- Barbara Lasseter First overflow
13709 15 Sep 2019 @ 1919 --- William first overflow
13699 15 Sep 2019 @ 0730 --- Barbara Lasseter First overflow
13677 13 Sep 2019 @ 0745 --- Barbara Lasseter 31 & foggy. No overflow. Audible boiling in the crater
13669 12 Sep 2019 @ 1544 --- Maureen Overflow start
13632 09 Sep 2019 @ 0710 --- Barbara Lasseter Mostly refilled. Still a little boiling at the edge
13626 08 Sep 2019 @ 0707 --- Barbara Lasseter First overflow
13623 07 Sep 2019 @ 2014 --- William no overflow by this time.
13585 05 Sep 2019 @ 1312 --- William first overflow
13541 04 Sep 2019 @ 1545 --- mhvogel One of co-workers told me the wrong overnight eruption time of GF. According to the Bluetooth download, the eruption time was 0440 which matches up with the dude that saw it at 0436. Sorry for the confusion.
13546 04 Sep 2019 @ 1306 --- mdschwarz Not in overflow. Parking lot full.
13496 01 Sep 2019 @ 1936 --- geysergaze Overflow 1936
13457 29 Aug 2019 @ 2029 --- steve Great Fountain was already in overflow. Start time unknown but the area of steaming water was still close to the main vent
13448 29 Aug 2019 @ 0856 --- steve First overflow, after a quick rise.
13440 28 Aug 2019 @ 0951 --- Maureen Overflow start.
13369 23 Aug 2019 @ 1840 --- Maureen Overflow start.
13360 23 Aug 2019 @ 0754 --- Maureen Overflow start.
13352 22 Aug 2019 @ 1840 --- William had not reached overflow at this time
13317 19 Aug 2019 @ 1135 --- Maureen Overflow start.
13311 18 Aug 2019 @ 1508 --- Maureen Overflow start.
13291 16 Aug 2019 @ 1634 --- William 1st overflow
13276 15 Aug 2019 @ 1812 --- William 1st overflow
13176 11 Aug 2019 @ 1945 --- minissa 1-2" from overflow, did not stay to confirm OF
13132 09 Aug 2019 @ 1356 09 Aug 2019 @ 1428 JSJ Inclinometer readings: highest water during 1st series about 81 feet; 2nd series about 59 feet; 3rd series about 45 feet.
12820 27 Jul 2019 @ 0618 --- Barbara Lasseter Overflow 0618
12560 22 Jul 2019 @ 1117 --- Barbara Lasseter Not in overflow
12521 19 Jul 2019 @ 0620 --- Barbara Lasseter Full to within 6-8inches of rim with low boil at north end
12512 18 Jul 2019 @ 0630 --- Barbara Lasseter Deep boiling with water visible only at the peak of the most vigorous boils
12500 16 Jul 2019 @ 0630 --- Barbara Lasseter Pool has refilled. Slight boil remains
12481 14 Jul 2019 @ 0750 --- Barbara Lasseter Overflow 0750
12480 14 Jul 2019 @ 0609 --- Barbara Lasseter Not in overflow
12462 13 Jul 2019 @ 0547 --- deanl Not in overflow yet
12254 05 Jul 2019 @ 0609 --- jkgood Light overflow
12101 04 Jul 2019 @ 0645 --- Barbara Lasseter Start of overflow. New prediction 0810 plus or minus 15 min
11904 21 Jun 2019 @ 0640 --- LynnS Very late in the eruption, thrashing around in the empty crater.
11889 19 Jun 2019 @ 1955 --- William in overflow when I arrived. ringed boil by 20:09.
11683 09 Jun 2019 @ 1024 --- LynnS Start of overflow
11653 08 Jun 2019 @ 0855 --- LynnS In early overflow; overflow coming out the east face but not trickling off first platform yet.
11639 07 Jun 2019 @ 2112 --- User34 Barely below overflow
11693 03 Jun 2019 @ 1726 --- Barbara Lasseter 74 minute overflow
11468 31 May 2019 @ 1956 31 May 2019 @ 2020 imapayne We arrived at great fountain around 1945 to a completely empty steaming crater. Standing on the benches, no water could be seen. At 1956, still no water. At 1957 the pool began to rise and by 2000 it was full and had a tiny trickle out the back, the pool held until 2011, but never really overflowed when it began to drop again. As it was late and the water was almost gone again, we decided to leave.
10278 18 Sep 2018 @ 1006 --- udo 724 victor announced prediction: 1240
10271 17 Sep 2018 @ 1645 --- ThomasR Post-eruptive, pool visible and sizzling at the edge.
10087 07 Sep 2018 @ 0930 --- Maureen VEC is now using 10 hr 45 m for middle of prediction window.
9886 26 Aug 2018 @ 0635 --- Barbara Lasseter first overflow
9884 26 Aug 2018 @ 0633 --- PamW Not in overflow.
9776 19 Aug 2018 @ 0650 19 Aug 2018 @ 0930 Glocho Maureen arrived this morning c. 06:50 and observed the end of Great Fountain. Gloria downloaded logger data at 9am with electronic eruption start time of 07:12. Since this directly contradicts Maureen's observation, I have removed this data point. The other data downloaded at the same time with the same device (08/18/18 1000E, 2021E) also did not match yesterday's observed eruptions, though I did download electronic times for yesterday and 8/17 PM through another device that appear to match.
9659 12 Aug 2018 @ 0720 --- Barbara Lasseter not yet in overflow
9625 11 Aug 2018 @ 0759 --- Barbara Lasseter 1st overflow
9591 10 Aug 2018 @ 0631 --- Barbara Lasseter within 2-3inches of rim
9503 07 Aug 2018 @ 0631 --- Barbara Lasseter boiling steam from deep in crater
9364 01 Aug 2018 @ 0754 --- rbwhitaker Well below overflow. Some small boiling on the north side.
9359 01 Aug 2018 @ 0636 --- Barbara Lasseter well below overflow, runoff channel dry
9338 31 Jul 2018 @ 0722 --- rbwhitaker Already in overflow when I arrived
9299 26 Jul 2018 @ 0101 --- billwarnock Maureen told me this afternoon that initial report of 0202E, which I posted this morning, was later determined to be 0101. She will post this time and this afternoon's eruption, which was around 1330, when she gets home.
9196 15 Jul 2018 @ 0605 --- Barbara Lasseter no visible water in crater. Runoff channel's wet.
9104 10 Jul 2018 @ 0936 --- udo NPS prediction 1845 via radio call on West repeater.
9094 10 Jul 2018 @ 0613 --- Micah Kipple In ovf
9073 08 Jul 2018 @ 2200 --- Kyle not in overflow
9035 05 Jul 2018 @ 0630 --- steve The morning eruption was finiished prior to 0630
8832 21 Jun 2018 @ 1200 --- Maureen Word from VEC is Firehole Lake Drive is open again!
8696 15 Jun 2018 @ 1238 15 Jun 2018 @ 1245 Maureen Initial overflow at 1238, that maintained until 1245, then dropped. Long false overflow.
8691 15 Jun 2018 @ 0832 --- DanS Post eruptive
8640 11 Jun 2018 @ 1920 --- DanS Not yet in overflow as of 1920
8612 09 Jun 2018 @ 2114 --- underarockphoto Overflow for 25m
8610 09 Jun 2018 @ 2100 --- Tara In early overflow. Left before eruption.
EntrySourceLinkComment
30 May 2018 @ 1726 EricZ https://static-geysercam-xyz.nyc3.digitaloceanspaces.com/GreatFountainGeyser.mp4 Video taken by tourist Grant Arinder
26 Jul 2017 @ 1752 JSJ https://www.flickr.com/photos/jsjgeology/36237239410 Photo (out of 10) of Great Fountain Geyser's 5:52 PM-onward eruption on 26 July 2017.
03 Jun 2017 @ 1832 JSJ https://www.flickr.com/photos/jsjgeology/34985316630 Photo (out of 9) of Great Fountain Geyser's evening eruption on 3 June 2017.
02 Jun 2017 @ 1645 JSJ https://www.flickr.com/photos/jsjgeology/35205457072 Photo (out of 7) of Great Fountain Geyser's late afternoon eruption on 2 June 2017.
02 Jun 2017 @ 1645 JSJ https://www.youtube.com/watch?v=UL1mwSjv1RY Time lapse video of Great Fountain Geyser's late afternoon eruption on 2 June 2017.
13 Aug 2016 @ 2027 JSJ https://www.youtube.com/watch?v=esB95f0I52U Time lapse video of Great Fountain Geyser's evening eruption on 13 August 2016.
13 Aug 2016 @ 2027 JSJ https://www.flickr.com/photos/jsjgeology/30109996042 Photo (1 of 7) of Great Fountain Geyser's evening eruption on 13 August 2016.
10 Aug 2016 @ 2018 JSJ https://www.flickr.com/photos/jsjgeology/30224237115 Photo (1 of 24) of Great Fountain Geyser's evening eruption on 10 August 2016.
10 Aug 2016 @ 2018 JSJ https://www.flickr.com/photos/jsjgeology/29594675523 Thermal image (1 of 3) of Great Fountain Geyser's evening eruption on 10 August 2016.
10 Aug 2016 @ 2018 JSJ https://www.youtube.com/watch?v=t4LIaXxRt0s Time lapse video of Great Fountain Geyser's evening eruption on 10 August 2016.
08 Sep 2014 @ 1505 Micah Kipple https://www.flickr.com/photos/sgplewka/15604440267 flickr
06 Sep 2014 @ 2003 Micah Kipple https://www.flickr.com/photos/wildwood4est/15368309463 flickr
13 Sep 2014 @ 1411 Micah Kipple https://www.flickr.com/photos/digbydachshund/15940278098 flickr
02 Jun 2014 @ 1303 Micah Kipple https://www.flickr.com/photos/125791209@N06/16128797716 flickr
25 Sep 2014 @ 1725 Micah Kipple https://www.flickr.com/photos/hhayk/16012608917 Flickr
24 Sep 2014 @ 1907 Micah Kipple https://www.flickr.com/photos/rtsmithcpa/15187347577 Flickr
24 Sep 2014 @ 1907 Micah Kipple https://www.flickr.com/photos/rtsmithcpa/15187166390 Flickr photo
19 Sep 2012 @ 1502 Jake http://www.youtube.com/watch?v=B3bTX5OQUEY a visitor\'s excellent video with the blue bubble at the 3 minute mark
Baseline does not exist.


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