Last Known Eruption
18d 14h 56m ago

Latest Eruptions

Eruption DurationInterval
08 Oct 2024 @ 17581h 27m
08 Oct 2024 @ 1631~1m 30d 22h 43m
07 Sep 2024 @ 17481m 20s 1h 32m
07 Sep 2024 @ 161644s 1h 39m
07 Sep 2024 @ 14371m 40s 1h 32m
07 Sep 2024 @ 13051m 5s 18d 22h 1m
19 Aug 2024 @ 15041h 46m
19 Aug 2024 @ 13181m 12s 1d 2h 39m
18 Aug 2024 @ 10392d 26m
16 Aug 2024 @ 1013 ie12d 23h 28m
03 Aug 2024 @ 10451h 2m
03 Aug 2024 @ 094315h 36m
02 Aug 2024 @ 180739d 7h 22m
24 Jun 2024 @ 10451h 59m
24 Jun 2024 @ 08461h 51m
24 Jun 2024 @ 065519h 46m
23 Jun 2024 @ 11094y 299d 20h 49m
29 Aug 2019 @ 14201h 54m
29 Aug 2019 @ 122617d 2h 5m
12 Aug 2019 @ 102140m
12 Aug 2019 @ 09415d 16h 47m
06 Aug 2019 @ 1654 maj26m
06 Aug 2019 @ 1628 min42m
06 Aug 2019 @ 1546 maj25m
06 Aug 2019 @ 1521 min33m
06 Aug 2019 @ 1448 maj1d 5h 0m
05 Aug 2019 @ 09481h 9m
05 Aug 2019 @ 08399d 16h 3m
26 Jul 2019 @ 16361m 54m
26 Jul 2019 @ 15421d 5h 18m
25 Jul 2019 @ 10245d 15h 11m
19 Jul 2019 @ 19131h 29m
19 Jul 2019 @ 1744~1.5m 3d 3h 24m
16 Jul 2019 @ 14201m 20h 31m
15 Jul 2019 @ 17491h 6m
15 Jul 2019 @ 16431h 6m
15 Jul 2019 @ 15371h 13m
15 Jul 2019 @ 142453m
15 Jul 2019 @ 13311h 6m
15 Jul 2019 @ 12251d 59m
14 Jul 2019 @ 11261y 255d 18h 41m
31 Oct 2017 @ 164535d 5h 2m
26 Sep 2017 @ 114312d 55m
14 Sep 2017 @ 10481m 6s 37m
14 Sep 2017 @ 10111m 8s 2d 20h 27m
11 Sep 2017 @ 13441d 22h 41m
09 Sep 2017 @ 1503<1m 2d 22h 55m
06 Sep 2017 @ 160854m
06 Sep 2017 @ 15141d1h 21m
06 Sep 2017 @ 135322m
06 Sep 2017 @ 133136m
06 Sep 2017 @ 125522h 37m
05 Sep 2017 @ 1418 maj38m
05 Sep 2017 @ 1340 maj27m
05 Sep 2017 @ 1313 min26m
05 Sep 2017 @ 1247 maj19h 8m
04 Sep 2017 @ 173930s 54m
04 Sep 2017 @ 1645 maj30s 23m
04 Sep 2017 @ 1622 min20s 35m
04 Sep 2017 @ 1547 maj21m
04 Sep 2017 @ 1526 min23m
04 Sep 2017 @ 1503 maj23m
04 Sep 2017 @ 1440 min26m
04 Sep 2017 @ 1414 maj23m
04 Sep 2017 @ 1351 min33m
04 Sep 2017 @ 1318 maj18h 7m
03 Sep 2017 @ 19111m 42m
03 Sep 2017 @ 18291m 2h 5m
03 Sep 2017 @ 16242d 3h 4m
01 Sep 2017 @ 1320<1m 40m
01 Sep 2017 @ 12402m 43m
01 Sep 2017 @ 1157 ns2m 6d 15h 36m
25 Aug 2017 @ 202121d 23m
04 Aug 2017 @ 19582d 4h 40m
02 Aug 2017 @ 151815m
02 Aug 2017 @ 150311m
02 Aug 2017 @ 145220m
02 Aug 2017 @ 143217m
02 Aug 2017 @ 141518m
02 Aug 2017 @ 135716m
02 Aug 2017 @ 134127d 23h 33m
05 Jul 2017 @ 14083d 2h 35m
02 Jul 2017 @ 113311m
02 Jul 2017 @ 112213m
02 Jul 2017 @ 110911m
02 Jul 2017 @ 105812d 55m
20 Jun 2017 @ 10035d 19h 28m
14 Jun 2017 @ 1435<30s 3h 25m
14 Jun 2017 @ 111021h 50m
13 Jun 2017 @ 13203d 22h 16m
09 Jun 2017 @ 150440s 3d 22h 10m
05 Jun 2017 @ 1654~0.5m 31m
05 Jun 2017 @ 1623~0.5m 23m
05 Jun 2017 @ 1600~0.5m 20m
05 Jun 2017 @ 1540~0.5m 23m
05 Jun 2017 @ 1517~0.5m 25m
05 Jun 2017 @ 1452~0.5m 22m
05 Jun 2017 @ 1430~0.5m 29m
05 Jun 2017 @ 1401~0.5m 23m
05 Jun 2017 @ 1338~0.5m 55m

Interval Statistics

Interval Count100
Min11m
Max4y 299d 20h 49m
Mean26d 19h 43m
Median1h 17m

Latest Notes

Note IDStart Time (US/Mountain)End Time (US/Mountain)EntrantNote
37563 13 Oct 2024 @ 1454 --- Janet Jones Ledge was clear, blue and overflowing when I arrived. Damp spots in the overflow channel on the side indicate it's still active. No standing water though, and checking on it again at about 1545 showed no change.
37265 29 Sep 2024 @ 1517 --- Janet Jones Arrived at Ledge to find it heavily overflowing and looking like it was ready to erupt, but giving it 5 minutes, I decided to continue documenting the basin through photos. It appears Ledge is still active based on dampness in the runoff channels. When I checked on it again at 1603, the water level was still at the same point, but overflow had lessened.
37111 21 Sep 2024 @ 1148 --- Janet Jones While I did not wait for it to erupt, the dampness and standing water in small depressions in the overflow channel indicate it is still active.
36853 07 Sep 2024 @ 1657 --- kc Quick rise to overflow with vigorous boiling, pool dropped
36852 07 Sep 2024 @ 1525 --- kc Quick rise to overflow with vigorous boiling, pool dropped
36851 07 Sep 2024 @ 1137 --- kc Pool was erupting 1 to 2 feet for 40 seconds but runoff didn't reach back left runoff channel
36708 02 Sep 2024 @ 1450 02 Sep 2024 @ 1715 Janet Jones I didn't really take any specific times as I was sharing information about West Thumb with a friend. The times listed here are an estimate of about when I was walking through the area, or in the area for 15-20 minute stretches. But...in three or four times that I went by, the runoff channel was sometime quite wet and the water level ranged from overflowing to below overflow. Everything indicates it was active today and my guess would be every 1-2 hours.
36639 30 Aug 2024 @ 1654 --- steve Runoff seen coming down the hill by Lakeshore from Ledge Spring
36629 30 Aug 2024 @ 1053 30 Aug 2024 @ 1330 Graham In overflow with continuous bubbling over main vent. Eruption channels dry. There was no noticeable change in activity for 2h and no eruption. 1330 still no eruption as I left the basin.
36472 19 Aug 2024 @ 1425 --- Craigmon99 Overflow stage 1: 1425 Eruptive vent showing signs of life 1431 Overflow stage 2: 1436 Overflow stage 3: 1443 “glass ceiling level” Eruptive vent was calm and nonexistent but came back 1444 After some fumbling around by the eruptive vent, eruption 1504
36471 19 Aug 2024 @ 1256 --- Craigmon99 Eruptive vent boiling vigorously
35752 06 Jul 2024 @ 1435 --- Janet Jones Ledge appears to still be active based on damp areas in the runoff channel where it would only be wet with an eruption.
35652 30 Jun 2024 @ 1102 --- Janet Jones Standing water in the overflow channels that could only have water in them from an eruption. Still active.
35526 24 Jun 2024 @ 1730 24 Jun 2024 @ 2035 Craigmon99 Walked up to heavy overflow and eruptive vent boiling. 1739 boiling ceased. Still in heavy overflow 1740 boiling over eruptive vent back on and strong. 1742 bowling ball diameter boil 1746 boil has weakened but pool level still looks good. Heavy overflow continues 1748 eruptive vent ceased. Central vent gently boiling. Heavy overflow continues 1752 eruptive vent boiling begins again. Overflow unchanged 1755 eruptive vent bowling ball sized and strong 1759 EV boil weakened substantially. Pool remains at good overflow. 1800 boil gone. Extremely windy out. Maybe effecting? Cannot say though 1803 EV on 1806 bowling ball sized heavy boil from EV 1810 EV boiling decrease drastically since heavy wind. Pool level still does increase with each push however. 1814 EV back on after blooping from central vent 1821 EV boil off. CV beginning gentle boil. For context, helicopter strong winds are in basin. One of the main directions however, is directly against the flooding action that starts at the beginning of an eruption. 1829 EV boil begins. Wind is lighter. 1831 Subaudible thumping sounds from Collapsing Pool 1835 EV Fail. Runoff remains heavy from main channel 1841 EV on. 1853 ev still on. Strong. Good push. Signs look good 1856 ev off. Spoke too soon! 1902 ev on 1912 ev off 1919 ev on 1925 ev off 1932 ev on 1930 ev off 1944 ev on 2021 ev still on variable. No eruption yet 2034 ev still on from last note. Heading out due to bugs and general hunger. Of note: Collapsing Pool’s overflow channel has water almost to boardwalk now.
35515 24 Jun 2024 @ 0917 --- Craigmon99 Pooling raising after last eruption. No overflow yet. Pool is pulsing upwards 0923 boiling has calmed, but pool continues to rise 0925: almost at overflow. Rolling boil in center occasionally 0927: overflow begins into main channel. Heavy push this time. No hesitance. 0929: heavy large splashy boil. Thought this was going to start eruption. Pool level dropped below overflow. 0931: pool continues bowling ball diameter boil. Still below overflow 0935: boil is still strong as if preeruptive but still below overflow 0940: boil weakening substantially over eruptive vent. Boil over central vent beginning and intermittent. 0956: in overflow. Light overflow 1000: medium overflow 1005: medium heavy overflow 1007: heavy overflow (both sides of far rock have flow) Occasional rolling boil from center continues. Nothing from eruptive vent since last mention 1010: convection from eruptive vent 1024: central vent more rolling boils. Eruptive vent a few bubbles seen but convection mostly 1029: central vent upwelling and rolling boil stronger 1034: eruptive vent boiling strong 1036: bowling ball size boil over eruptive vent
35490 23 Jun 2024 @ 1043 --- Janet Jones Ledge still below overflow. I left to document the lower section of the basin.
35489 23 Jun 2024 @ 1029 --- Janet Jones Ledge was below overflow, however water stood in many places in the wide area where water overflows when an eruption occurs - indicating it's possibly active. I went to finish photo documentation of the upper half with a plan to check back before documenting the lower half.
34761 30 May 2024 @ 0909 --- Graham In steady overflow and hot. No indication of eruption recently, washbarea is dry and lots of small decayed sinter.
34501 10 May 2024 @ 1305 --- Janet Jones Steady overflow with microbes growing in the overflow channel. Blue, clear water and bubbles rising steadily. Was there for five minutes with no change in behavior.
26928 08 Jul 2023 @ 1556 --- nails Many feet below overflow. Water is brown with some green color. Occasional bubbles.
24243 05 Oct 2022 @ 1317 --- WillBoekel not active has green bacteria growing around edge
23357 23 Aug 2022 @ 0830 --- Craigmon99 Bench in between collapsing spring and ledge spring wet. Rest of boardwalk dry
16104 13 Sep 2020 @ 1205 --- Graham Very low water level. inactive
13721 16 Sep 2019 @ 1009 --- Janet Jones Rangers at West Thumb reported that Ledge's water level started to drop last week and is now down further. When I arrived there today, it was still a clear hot blue color with bubbles rising, but the water level was about half full - a level it has been at often in the past. I did not stay to observe whether or not it might still be erupting from a lower pool. Percolating Spring was still overflowing and percolating away. Thermal features across the boardwalk (Thumb Geyser, "Waterfall," etc) had fewer microbes and slightly elevated water levels as compared to my last visit.
13599 06 Sep 2019 @ 1320 06 Sep 2019 @ 1520 Graham In overflow with very small rise and fall in the pool level. No eruption.
12531 19 Jul 2019 @ 1837 --- User34 First overflow
11475 01 Jun 2019 @ 1320 01 Jun 2019 @ 1530 Graham Starting overflow with periodic boiling about every 10 min. Still in overflow with slightly stronger boils at 1530.
11201 10 May 2019 @ 1237 --- Janet Jones It’s alive! Hot, full, boiling, and overflow channel is damp.
10915 26 Jan 2019 @ 0945 26 Jan 2019 @ 1105 Graham Runoff area is washed. Pool rose from below overflow to overflow and boiling over the vent started after 1040. Could erupt any time.
4537 25 Jul 2017 @ 1844 --- JSJ Damp runoff areas. Didn't stay to watch for eruptions (boardwalk closed for construction).
4123 23 May 2017 @ 0842 --- Janet Jones Hot, full, boiling and the runoff channel is wet. Runoff channel carved all the way to the lower boardwalk.
4101 19 May 2017 @ 1805 --- Tara Looked post eruptive.
15277 26 Aug 1996 @ 0000 26 Aug 1996 @ 2359 JarnoO erupted today
EntrySourceLinkComment
05 Jun 2017 @ 1243 JSJ https://www.youtube.com/watch?v=M_9OOpeSwvs#t=5m58s Video (time stamp 5:58 to 6:53) of Ledge Spring's 12:43 to 12:44 PM eruption on 5 June 2017. The previous clip & the following 9 clips show other eruptions that afternoon.
01 Jun 2017 @ 1908 JSJ https://www.youtube.com/watch?v=M_9OOpeSwvs#t=2m59s Video (time stamp 2:59 to 3:40) of Ledge Spring's 7:08 to 7:09 PM eruption on 1 June 2017. The previous 3 clips & the following clip show other eruptions that evening.
05 Jun 2017 @ 1654 JSJ https://www.flickr.com/photos/jsjgeology/35324545101 Photo (out of 8) of Ledge Spring's 4:54 PM eruption on 5 June 2017.
05 Jun 2017 @ 1623 JSJ https://www.flickr.com/photos/jsjgeology/35414575446 Photo (1 of 5) of Ledge Spring's 4:23 PM eruption on 5 June 2017.
01 Jun 2017 @ 1908 JSJ https://www.flickr.com/photos/jsjgeology/35286506702 Photo (out of 11) of Ledge Spring's 7:08 to 7:09 PM eruption on 1 June 2017.
01 Jun 2017 @ 1846 JSJ https://www.flickr.com/photos/jsjgeology/35286199072 Photo (out of 12) of Ledge Spring's 6:46 PM eruption on 1 June 2017.
01 Jun 2017 @ 1830 JSJ https://www.flickr.com/photos/jsjgeology/35285663602 Photo (out of 7) of Ledge Spring's 6:30 PM eruption on 1 June 2017.
Baseline does not exist.