Newest Volcano Notice Including Yellowstone

Summary

Yellowstone Caldera activity remains at background levels, with 100 located earthquakes in January (largest = M2.6). Deformation measurements indicate continued subtle uplift along the north caldera rim, as well as the onset of caldera subsidence in late December.

Recent Work and News

At least two small eruptions occurred at Black Diamond Pool in Biscuit Basin, site of a hydrothermal explosion in 2024. The eruptions occurred on January 19 and 24 and were detected by infrasound and seismic monitoring, but camera views were obscured (by darkness and ice) at the times of the events.

Seismicity

During January 2026, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, located 100 earthquakes in the Yellowstone National Park region. The largest event of the month was a microearthquake of magnitude 2.6 located about 5 miles west-northwest of West Yellowstone, Montana, on January 10 at 12:06 p.m. MST.

January seismicity in Yellowstone was marked by two swarms:

1. A swarm of 10 earthquakes took place approximately 16 miles west-northwest of Lake, in Yellowstone National Park, during January 4–9. The largest earthquake in the sequence was a magnitude 1.8 event on January 9 at 2:01 a.m. MST.

2. A swarm of 13 earthquakes occurred approximately 12 miles northeast of Old Faithful, in Yellowstone National Park, on January 26. The largest earthquake in the sequence was a magnitude 2.1 at 6:31 a.m. MST on that date.

Earthquake activity in Yellowstone is at background levels.

Ground Deformation

Continuous GPS stations indicate continued uplift centered on the north caldera rim to the south of Norris Geyser Basin, although the rate may have slowed over the past few months compared to the rate at the onset of the deformation in July 2025.  In Yellowstone Caldera, continuous GPS data appear to indicate the end of seasonal uplift in late December.  Since overall caldera subsidence began in 2015, seasonal uplift (caused by groundwater and runoff conditions) usually starts in May or June and lasts until September or October, but the transition back to subsidence took longer in 2025.

An example of GPS data can be found at http://www.unavco.org/instrumentation/networks/status/pbo/data/NRWY (click on Static Plots / Cleaned)