Last Known Eruption
44d 12h 5m ago

Latest Eruptions

Eruption DurationInterval
04 Apr 2022 @ 0742 ie wc69d 6h 42m
25 Jan 2022 @ 0000 A6d 18h 53m
18 Jan 2022 @ 0507 ie wc4d 15h 55m
13 Jan 2022 @ 131232m 9d 1h 5m
04 Jan 2022 @ 1207 ie wc16d 7h 45m
19 Dec 2021 @ 0422 wc9d 15h 0m
09 Dec 2021 @ 1322 ie wc11d 2h 9m
28 Nov 2021 @ 1113 wc7d 3h 10m
21 Nov 2021 @ 0803 ns wc12d 14h 16m
08 Nov 2021 @ 1747 ? ie wc14d 18h 47m
25 Oct 2021 @ 0000 A3d 2h 32m
21 Oct 2021 @ 2128 wc3d 14h 22m
18 Oct 2021 @ 0706 ns wc3d 13h 51m
14 Oct 2021 @ 171539m 3d 23h 3m
10 Oct 2021 @ 181235m 5d 18h 12m
05 Oct 2021 @ 0000 A12d 2h 34m
22 Sep 2021 @ 212637m 4d 8h 35m
18 Sep 2021 @ 125137m 4d 20h 26m
13 Sep 2021 @ 1624:1734m 0s 2d 9h 10m 22s
11 Sep 2021 @ 0713:55~28m 3d 15h 17m
07 Sep 2021 @ 155639m 4d 21h 30m
02 Sep 2021 @ 182626m 2d 13h 18m
31 Aug 2021 @ 0508 wc3d 16h 5m
27 Aug 2021 @ 130331m 3d 10h 30m
24 Aug 2021 @ 0233 wc6d 3h 25m
17 Aug 2021 @ 230834m 5d 5h 44m
12 Aug 2021 @ 172433m 2d 19h 32m
09 Aug 2021 @ 2152 wc3d 5h 29m
06 Aug 2021 @ 162336m 5d 20h 54m
31 Jul 2021 @ 192930m 3d 17h 49m
28 Jul 2021 @ 0140 A wc4d 18h 43m
23 Jul 2021 @ 065729m 4d 6h 57m
19 Jul 2021 @ 0000 A2d 11h 49m
16 Jul 2021 @ 121132m 5d 22h 12m
10 Jul 2021 @ 135936m 5d 1h 52m
05 Jul 2021 @ 12073d 14h 14m
01 Jul 2021 @ 2153 ns4d 8h 19m
27 Jun 2021 @ 133432m 7d 5h 0m
20 Jun 2021 @ 083437m 7d 14h 40m
12 Jun 2021 @ 175428m 4d 16h 54m
08 Jun 2021 @ 0100 A5d 15h 20m
02 Jun 2021 @ 0940 ie wc16d 8h 9m
17 May 2021 @ 0131 ie wc6d 23h 34m
10 May 2021 @ 0157 wc8d 1h 57m
02 May 2021 @ 0000 ? A5d 16h 53m
26 Apr 2021 @ 0707 wc7d 8h 24m
18 Apr 2021 @ 2243 wc82d 1h 15m
26 Jan 2021 @ 2028 wc83d 3h 47m
04 Nov 2020 @ 1641 ie wc5d 2h 36m
30 Oct 2020 @ 1505 ie wc53d 16h 20m
06 Sep 2020 @ 2245 E6d 22h 4m
31 Aug 2020 @ 0041 ie wc20d 17h 46m
10 Aug 2020 @ 0655 wc1y 289d 20h 53m
25 Oct 2018 @ 1002 wc6d 20h 22m
18 Oct 2018 @ 1340 ie wc7d 13h 36m
11 Oct 2018 @ 0004 E4d 3h 0m
06 Oct 2018 @ 2104 E6d 5h 30m
30 Sep 2018 @ 1534 E3d 7h 27m
27 Sep 2018 @ 080733m 5d 9h 25m
21 Sep 2018 @ 2242 wc4d 11h 18m
17 Sep 2018 @ 1124 E3d 12h 40m
13 Sep 2018 @ 2244 E18d 15h 12m
26 Aug 2018 @ 0732 wc3d 13h 4m
22 Aug 2018 @ 182835m 5d 6h 34m
17 Aug 2018 @ 1154 E10d 6h 59m
07 Aug 2018 @ 0455 wc3d 10h 11m
03 Aug 2018 @ 1844 E4d 9h 56m
30 Jul 2018 @ 084837m 8d 9h 42m
21 Jul 2018 @ 230634m 8d 20h 27m
13 Jul 2018 @ 0239 wc5d 5m
08 Jul 2018 @ 0234 E6d 9h 17m
01 Jul 2018 @ 171734m 6d 8h 48m
25 Jun 2018 @ 0829 ns38m 11d 4h 19m
14 Jun 2018 @ 0410 wc7d 14h 52m
06 Jun 2018 @ 131832m 75d 21h 14m
22 Mar 2018 @ 1604 E3d 10h 9m
19 Mar 2018 @ 0555 wc5d 16h 11m
13 Mar 2018 @ 1344 E7d 15h 20m
05 Mar 2018 @ 2124 E4d 11h 50m
01 Mar 2018 @ 0934 E4d 4h 30m
25 Feb 2018 @ 0504 E6d 4h 30m
19 Feb 2018 @ 0034 E2d 21h 40m
16 Feb 2018 @ 0254 E5d 20h 40m
10 Feb 2018 @ 0614 E6d 4h 0m
04 Feb 2018 @ 0214 E4d 11h 51m
30 Jan 2018 @ 142332m 4d 21h 29m
25 Jan 2018 @ 1654 E6d 12h 30m
19 Jan 2018 @ 0424 E7d 13h 40m
11 Jan 2018 @ 1444 E11d 9h 46m
31 Dec 2017 @ 0458 wc4d 11h 4m
26 Dec 2017 @ 1754 E10d 18h 50m
15 Dec 2017 @ 2304 E11d 18h 30m
04 Dec 2017 @ 0434 E10d 15h 50m
23 Nov 2017 @ 1244 E6d 12h 10m
17 Nov 2017 @ 0034 E6d 4h 25m
10 Nov 2017 @ 2008:40 E5d 18h 5m 0s
05 Nov 2017 @ 0203:40 E5d 4h 51m
30 Oct 2017 @ 2212 wc7d 7h 53m
23 Oct 2017 @ 1418:40 E8d 3h 24m
15 Oct 2017 @ 10546d 10h 54m

Interval Statistics

Interval Count100
Min2d 9h 10m
Max1y 289d 20h 53m
Mean16d 9h 11m
Median5d 21h 33m

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
20745 21 Jan 2022 @ 1635 --- BrandonC No signs of eruption yet
20750 20 Jan 2022 @ 1740 --- BrandonC No eruption yet
20660 10 Jan 2022 @ 2036 --- K.Cooper Possible eruption time, ie, at this time. Steam coming from the right location (mostly right location at least), steam drifting in from the right. It is a possible eruption but due to the darkness, as well as the possibility of this being a post eruptive Grand, I am leaving as a note for now.
20600 04 Dec 2021 @ 1613 --- Betty Lots of steam from the correct position, though windblown. Not sure it is an eruption.
20236 31 Oct 2021 @ 0919 --- cb no overnight eruption. boardwalks dry, angle on but Mortar catch basin still has water.
20230 30 Oct 2021 @ 1725 --- DanS No eruption. Unattended.
20221 30 Oct 2021 @ 1430 --- DanS Has not erupted. Activity switched from lower Mortar to Fan around 1355.
20215 30 Oct 2021 @ 0920 --- User34 Catchbasins on Mortar are full, and there are fresh flow channels in the gravel in Main's line of fire. Angle is in marathon
20208 29 Oct 2021 @ 1645 --- DanS No eruption as of 1645
20187 29 Oct 2021 @ 1055 --- DanS Confirm no eruption yet.
20183 29 Oct 2021 @ 0920 --- aferrara Does not appear to have erupted overnight. I welcome a second opinion if anyone else comes out this way.
20164 28 Oct 2021 @ 1747 --- DanS No eruption yet. Unattended.
20157 28 Oct 2021 @ 1035 --- DanS No eruption yet.
20153 27 Oct 2021 @ 1725 --- DanS No eruption yet. Unattended. Cycling with some nice action in lower Mortar.
20152 27 Oct 2021 @ 1638 --- DanS YNP crew replacing signs for F&M
20077 22 Oct 2021 @ 0840 --- Tara Area wet, catchbasins full
20076 21 Oct 2021 @ 1905 --- Tara Unattended.
20069 21 Oct 2021 @ 0845 --- Tara No signs of recent eruption
20014 17 Oct 2021 @ 0940 --- Tara No sign of recent eruption.
19942 10 Oct 2021 @ 0240 --- Dan A Came down to F&M in time to check on it and saw upper mortar surging slightly over the cone with water coming out the crack. It had several of these surges. Likely the end of an event cycle. The next event cycle whenever that is will probably result in an eruption. That is probably not guaranteed though.
19940 09 Oct 2021 @ 0712 --- Dan A Good news everybody fan and mortar didn’t erupt overnight.
19936 08 Oct 2021 @ 0801 --- Dan A No eruption overnight
19886 05 Oct 2021 @ 0812 --- Darcie Erupted overnight/early morning. Catch basins are full, and boardwalk and trail are wet
19862 03 Oct 2021 @ 0752 --- ddshepard No eruption overnight
19860 02 Oct 2021 @ 0730 02 Oct 2021 @ 1823 ddshepard No eruption yet. Continued pattern of this interval of mostly weak Regular Cycles with occasional better ones with variable water levels
19845 02 Oct 2021 @ 0649 --- SteveO No eruption yet, left unattended.
19823 01 Oct 2021 @ 0756 --- Brian No overnight eruption
19820 30 Sep 2021 @ 1940 --- Tara Unattended.
19796 29 Sep 2021 @ 2045 --- Tara Unattended.
19773 28 Sep 2021 @ 2035 --- Tara Unattended
19732 25 Sep 2021 @ 2300 --- Tara Unattended.
19681 22 Sep 2021 @ 0656 --- Graham No eruption yet.
19679 21 Sep 2021 @ 1938 --- Brian Unattended
19671 21 Sep 2021 @ 0655 --- Graham No eruption yet.
19639 18 Sep 2021 @ 0651 --- Graham No eruption yet.
19629 17 Sep 2021 @ 0652 --- Graham No eruption overnight
19628 16 Sep 2021 @ 2320 --- Tara Unattended. Still in Angle mode
19595 16 Sep 2021 @ 0657 --- Graham No eruption overnight.
19412 10 Sep 2021 @ 0643 --- Graham No eruption yet. No Angle either!
19344 07 Sep 2021 @ 0545 --- hkoenig no overnight eruption.
19325 06 Sep 2021 @ 0555 --- hkoenig Angle!! And no eruption overnight
19323 05 Sep 2021 @ 2047 --- Tara Unattended, still Angle marathon
19312 05 Sep 2021 @ 0654 --- Graham No evidence of an eruption yet.
19161 30 Aug 2021 @ 0925 --- Tara No eruption yet, catchbasins and boardwalk dry.
19095 27 Aug 2021 @ 0525 --- Dan A No eruption yet
19003 23 Aug 2021 @ 0551 --- Dan A No eruption yet
18982 22 Aug 2021 @ 0549 --- Dan A No eruption yet.
18972 21 Aug 2021 @ 0637 --- Dan A No eruption yet
18950 17 Aug 2021 @ 0502 --- Dan A No eruption yet
18947 16 Aug 2021 @ 0558 --- JimS No eruption yet.
18939 15 Aug 2021 @ 0617 --- JimS No eruption yet.
18879 10 Aug 2021 @ 0023 --- deanl erupted overnight. see my A time from 8/9.
18844 06 Aug 2021 @ 0620 --- JimS No eruption yet.
18835 05 Aug 2021 @ 0552 --- JimS No eruption yet.
18833 04 Aug 2021 @ 2110 --- Brian Unattended as of 2110
18820 04 Aug 2021 @ 0553 --- JimS No eruption yet.
18566 21 Jul 2021 @ 2304 --- William unattended
18518 19 Jul 2021 @ 0825 --- deanl Fan & Mortar are very quiet and the boardwalk is wet. They likely erupted overnight
18489 15 Jul 2021 @ 2000 --- Tara Unattended, storm moving in
18427 14 Jul 2021 @ 2100 --- Tara Unattended
18314 09 Jul 2021 @ 0601 --- JimS No eruption yet.
18309 08 Jul 2021 @ 0607 --- JimS No eruption yet.
18253 03 Jul 2021 @ 0556 --- JimS BV sending water nearly to the river and LM splashing. Lots of steam from MV.
18214 01 Jul 2021 @ 0607 --- JimS No eruption yet.
18109 27 Jun 2021 @ 0548 --- JimS No eruption overnight.
18107 26 Jun 2021 @ 2211 --- William unattended
18100 26 Jun 2021 @ 0551 --- JimS No eruption yet.
18068 24 Jun 2021 @ 0630 24 Jun 2021 @ 0659 JimS Disorganized splashing followed by Angle solo.
17943 20 Jun 2021 @ 1200 --- WillBoekel system showing normal signs of an eruption previous. 3.5hrs after eruption vents of fan drying and turning white. only a slight waft of steam from upper mortar.
17936 20 Jun 2021 @ 0542 --- JimS No eruption yet.
17900 19 Jun 2021 @ 0557 --- JimS No eruption yet. Vents are steaming. BV splashing.
17894 18 Jun 2021 @ 2230 --- William unattended
17896 18 Jun 2021 @ 1424 18 Jun 2021 @ 1926 Polly Overall, F&M were having long cycles. Bottom Vent and Lower Mortar showed water splashing on many cycles. Upper Mortar grumbled or roared on some of the cycles, and water was seen occasionally. Fan had better water levels than were seen on previous days. Angle often came on or splashed before Gold came on. Main Vent was steamy at times, and we heard a couple of roars. Only one small splash in MV was seen.
17878 18 Jun 2021 @ 0552 --- JimS No eruption yet. Just winding up a cycle now.
17741 13 Jun 2021 @ 0950 --- JimS Bottom vent was erupting to the river at this time.
17732 12 Jun 2021 @ 1510 12 Jun 2021 @ 1644 Graham Here is the garbage activity that preceded the event cycle and subsequent eruption. 1510 RV off, AV ie. 1517 everything coughed on and off. 1519 everything coughed on and off, AVstill ie. 1528 everything on. 1543 RV off, and back on several times with AV ie. 1553 RV off, AV ie. 1604 AV off. 1614 AV on. 1620 RV and AV on. 1621 GV on. 1640 RV off, AV ie. 1644 RV cough.
17697 12 Jun 2021 @ 1005 12 Jun 2021 @ 1027 Polly A already off, 1005 RH, 1006 G 1010 G pause 1015 BV spritzing, brief low water LM !1017 Angle on full! 1020 RH back on AC
17690 12 Jun 2021 @ 0625 12 Jun 2021 @ 0731 JimS All cycles disorganized.
17686 11 Jun 2021 @ 2100 11 Jun 2021 @ 2130 William continued disorganization
17675 11 Jun 2021 @ 1907 --- Graham Garbage for the last hour, short cycles, vents on in the wrong order. 1754 RV already off. 1805 AV last splash. 1810 one AV splash. 1815 RV and AV on. 1818 GV on. 1822 RV off. 1825 RV and AV on, then Gold. 1835 RV and AV off. 1840 RV, AV, and then GV on. 1854 RV off AV ie. 1904 RV  on, AV still ie.
17673 11 Jun 2021 @ 1700 --- Polly Unattended
17653 11 Jun 2021 @ 0657 --- JimS Angle solo.
17596 09 Jun 2021 @ 0659 --- CraigC blast of horizontal water in Main Vent while High and Gold splashing sporadically
17515 06 Jun 2021 @ 0950 06 Jun 2021 @ 1930 Graham No event cycles during this time. All cycles were well organized with River on before Gold on before Angle on and Angle turned off each cycle, usually within 10 minutes of River turning off. Main Vent steamed a lot but never had forced huffing or splashes. A couple of cycles had good water levels as long as 14m after Gold turned on but most did not. Upper Mortar only splashed once in the cone on the strongest cycle.
17469 05 Jun 2021 @ 0831 --- CraigC Bottom Vent ie, runoff halfway to river
17429 04 Jun 2021 @ 1034 --- CraigC Bottom Vent ie, runoff to river
17372 02 Jun 2021 @ 1010 --- JimS End of water phase
17331 01 Jun 2021 @ 1150 --- Graham Angle marathon continues.
17233 28 May 2021 @ 1900 --- Ben VL Angle. Saw some light splashing from BV this time.
17200 27 May 2021 @ 0825 27 May 2021 @ 1300 Suzanne Angle Vent continued its sporadic splashing. No good cycles seen.
17193 26 May 2021 @ 1721 --- Ben VL Angle show continues. I think F&M may have realized what month it is.
17186 25 May 2021 @ 2116 --- Ben VL Unattended. Watched for an hour ish. Been getting nothing but Angle garbage every evening when I've watched it for the last three days.
16929 27 Apr 2021 @ 0934 --- CraigC Bottom vent ie, runoff halfway to Firehole
16917 25 Apr 2021 @ 1258 --- CraigC there is some water in the upper catch basin on Mortar, probably less than half full. indication on runoff channel of Main does not confirm an eruption
16165 18 Sep 2020 @ 0740 --- CraigC Angle splashing, everything else huffing or puffing in the system
16160 18 Sep 2020 @ 0528 --- Graham Currently in garbage mode. Angle on and River turning on and off with occasional participation by Gold. 0554 River off Angle still on. All on 0606. Departed for breakfast.
16252 10 Sep 2020 @ 1300 --- Graham Water in the UM catch basins and no rain recently (snow on evening of the 7th was the last precip). Unknown when it may have erupted but water was reported present this morning. Probably from the eruption late on 6th from the monitor.
15904 31 Aug 2020 @ 0900 --- CraigC boardwalk wet between Spiteful and trees to the North. Water in Upper Mortar catch basins.
15720 24 Aug 2020 @ 0654 --- underarockphoto Heavy steam from that area on the webcam. Not enough oomph for eruption, but could be recently post eruptive...?
15513 11 Aug 2020 @ 1116 --- CraigC observed what appeared to be a regular event cycle, including 9 min full eruption of bottom vent, accompanied by much splashing in main vent with eventual normal turn on of river at 11:56 high gold at 11:58 Angle at 12:09, the vents off at 12:14
EntrySourceLinkComment
13 Sep 2021 @ 1624 Tara https://youtu.be/SriD_M5k2hQ Video of eruption by Tara Cross.
27 Jun 2021 @ 1334 Tara https://youtu.be/yFbVqS3i8yc Video of eruption by Tara Cross.
20 Jun 2021 @ 0834 Tara https://youtu.be/27nF0KIAt9s Video of eruption by Tara Cross.
02 Sep 2021 @ 1826 Tara https://youtu.be/hzkdexYf-Yc Video of eruption by Tara Cross.
24 Aug 2021 @ 0233 Tara https://youtu.be/kohfkNVhvDI?t=525 overnight webcam capture showing Fan and Mortar steam cloud at 0233
09 Aug 2021 @ 2152 Tara https://youtu.be/pAbQFfYkE6I?t=71 overnight webcam capture showing Fan and Mortar steam cloud at 2152
24 Aug 2021 @ 0233 JoeN https://youtu.be/NTOAh5LI5Ns F&M video
02 Jun 2021 @ 0940 JoeN https://youtu.be/SzszlKWaG9k F&M video
26 Apr 2021 @ 0707 JoeN https://i.imgur.com/78YCoLM.png start and in progress
26 Apr 2021 @ 0707 JoeN https://i.imgur.com/78YCoLM.png Start and in progress
18 Apr 2021 @ 2243 JoeN https://youtu.be/cEMy4JNZ6EE Fan & Mortar ~2243:50 Bonus Lion and Aurum
26 Jan 2021 @ 2028 JoeN https://youtu.be/EFhzZMlIcPw Fan & Mortar video
26 Jan 2021 @ 2028 K.Cooper https://youtu.be/aTzHnPw7yc8 Few minutes of F&M, video by Linda Gangi.
26 Jan 2021 @ 2034 ltgangi https://youtu.be/aTzHnPw7yc8 F&M
30 Oct 2020 @ 1505 JarnoO https://www.youtube.com/watch?v=2poGwom5GkM As seen from the webcam.
31 Aug 2020 @ 0041 JoeN https://youtu.be/9YPisj8Lx-g F&M as seen from NPS Camera
10 Aug 2020 @ 0710 JoeN https://www.youtube.com/watch?v=R5yPZ8CcfEg CraigC video
10 Aug 2020 @ 0655 JoeN https://www.youtube.com/watch?v=R5yPZ8CcfEg CraigC video
10 Aug 2020 @ 0655 JoeN https://youtu.be/MqyYPz67QZE F&M replay
06 Jun 2018 @ 1318 JSJ https://www.youtube.com/watch?v=V6v-pWJqTwY#t=5m47s Clips 18-27 of this video compilation (= time stamp 5:47 to the end) show some of Fan Geyser’s 1:18 to 1:52 PM major eruption on 6 June 2018.
BaselineDistance (ft)Description
Rock 100Both markers are on a rock behind the benches on the upstream side of the path