Fremont County Emergency Management

Fremont County Emergency Management A central repository for community planning & preparedness and real-time emergency information.

06/01/2026

YELLOWSTONE VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Monday, June 1, 2026, 10:55 AM MDT (Monday, June 1, 2026, 16:55 UTC)

YELLOWSTONE VOLCANO (VNUM #325010)
44°25'48" N 110°40'12" W, Summit Elevation 9203 ft (2805 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Summary: YVO Monthly Update: background seismicity and deformation

Summary
Yellowstone Caldera activity remains at background levels, with 45 located earthquakes in May (largest = M2.0). Deformation measurements indicate no significant uplift or subsidence of the caldera or north caldera rim since January 2026.

Recent Work and News
Echinus Geyser, in Norris Geyser Basin, remained active, with 2 eruptions in May. The month also included eruptions of Black Diamond Pool in Biscuit Basin (site of a hydrothermal explosion in 2024) that were recorded by acoustic, seismic, and temperature measurements on May 5 and 11. The biennial coordination meeting of the Yellowstone Volcano Observatory took place during May 18-20 at Mammoth Hot Springs, with discussions focusing on how to update geologic maps of the park and better anticipate and detect hazardous hydrothermal events. Field work included the seasonal deployment of semipermanent GPS stations, which are temporary GPS sites that are set up every May and recovered in September/October and serve to densify the ground deformation monitoring network during summer months.

Seismicity
During May 2026, the University of Utah Seismograph Stations, responsible for the operation and analysis of the Yellowstone Seismic Network, located 45 earthquakes in the Yellowstone National Park region. The largest event of the month was a microearthquake of magnitude 2.0 located about 20 miles south-southeast of Mammoth Hot Springs in Yellowstone National Park on May 21 at 11:08 p.m. MDT.
There were no swarms identified during May.
Earthquake activity in Yellowstone is at background levels.

Ground Deformation
Data from continuous GPS stations indicate little net deformation in the region since January 2026. The uplift that started in July 2025 on the north caldera rim ceased by mid-January 2026, and there has been no uplift or subsidence of Yellowstone Caldera since December 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)


The Yellowstone Volcano Observatory (YVO) provides long-term monitoring of volcanic and earthquake activity in the Yellowstone National Park region. Yellowstone is the site of the largest and most diverse collection of natural thermal features in the world and the first National Park. YVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.

YVO Member agencies: USGS, Yellowstone National Park, University of Utah, University of Wyoming, Montana State University, Earthscope Consortium, Wyoming State Geological Survey, Montana Bureau of Mines and Geology, Idaho Geological Survey

CONTACT INFORMATION:

Michael Poland, Scientist-in-Charge
[email protected]

Are you prepared?Sign up for local emergency alerts here: https://public.alertsense.com/SignUp/?RegionId=1089
06/01/2026

Are you prepared?

Sign up for local emergency alerts here: https://public.alertsense.com/SignUp/?RegionId=1089

As wildfire season heats up across Idaho, emergency officials are urging residents to sign up for alerts, prepare go-bags, and plan evacuation routes before a fire threatens their neighborhood.

05/30/2026

This Wildfire Awareness Month, take steps to prevent fires! During critical fire weather, don't burn yard waste & debris or do any activity that may cause sparks. Strengthen your home against wildfires with tips from ready.gov/wildfires

Last night around 7 pm, a fast-moving wildfire started southwest of Mountain Home.  The fire was brought under control a...
05/27/2026

Last night around 7 pm, a fast-moving wildfire started southwest of Mountain Home. The fire was brought under control at 10 pm and limited to 250 acres, but 16 homes were destroyed. Six officers were injured while performing evacuations.

Wildfires don’t have to be thousands of acres to be deadly or burn multiple homes and can happen quickly.

Do you know what to do if you must evacuate right now? Do you have a “Go Kit” that is near your door or in your car? Where will you go? How will you stay in touch with family members?

05/26/2026

412 PM MDT Tue May 26 2026
..A STRONG THUNDERSTORM WILL IMPACT EAST CENTRAL FREMONT COUNTY
THROUGH 445 PM MDT...

At 410 PM MDT, Doppler radar was tracking a strong thunderstorm 12
miles southwest of Mystic Falls, or 13 miles west of Old Faithful,
moving north at 30 mph.

HAZARD...Wind gusts in excess of 35 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to outdoor objects is
possible.

Locations impacted include...
Big Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

BULLETIN - IMMEDIATE BROADCAST REQUESTEDSevere Thunderstorm WarningNational Weather Service Pocatello ID341 PM MDT Tue M...
05/26/2026

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pocatello ID
341 PM MDT Tue May 26 2026

The National Weather Service in Pocatello has issued a

* Severe Thunderstorm Warning for...
East central Fremont County in southeastern Idaho...

* Until 415 PM MDT.

* At 340 PM MDT, a severe thunderstorm was located 18 miles northeast
of Drummond, or 19 miles northeast of Marysville, moving north at
30 mph.

HAZARD...Half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

* This severe thunderstorm will remain over mainly rural areas of
east central Fremont County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

For your protection move to an interior room on the lowest floor of a
building.

BULLETIN - IMMEDIATE BROADCAST REQUESTEDSevere Thunderstorm WarningNational Weather Service Pocatello ID300 PM MDT Tue M...
05/26/2026

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pocatello ID
300 PM MDT Tue May 26 2026

The National Weather Service in Pocatello has issued a

* Severe Thunderstorm Warning for...
Northeastern Teton County in eastern Idaho...
Southeastern Fremont County in southeastern Idaho...

* Until 345 PM MDT.

* At 259 PM MDT, a severe thunderstorm was located over Felt, moving
north at 30 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

* Locations impacted include...
Marysville, Felt, Tetonia, Drummond, Warm River, Tetonia Research
Station, and Ashton Hill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Eastern Idaho is facing a severe early wildfire season fueled by record-low snowpack and critical drought.  Abnormally h...
05/26/2026

Eastern Idaho is facing a severe early wildfire season fueled by record-low snowpack and critical drought. Abnormally high spring temperatures melted the snowpack early, and vegetation is dry across eastern Idaho.

The 1988 Yellowstone Fires were one of the defining events in modern U.S. wildfire policy, resulting from a perfect storm of extreme multi-year drought, high erratic winds, and a massive accumulation of dry, combustible timber. The North Fork Fire—which started in the Targhee National Forest and burned 14,417 acres within Fremont County—was the largest fire burning 550,000 acres that year.

Compare the conditions between 1988 and today:

1988 Conditions
• The Greater Yellowstone ecosystem only received 30% of normal winter snowfall
• Virtually no rainfall June through August
• Live fuel moisture plunged to 3% and dead fuel moisture to 5%. Note: kiln dried lumber moisture content is 12%.

Today’s conditions
• Snow water equivalent for the Henrys Fork Basin is 33%
• 100-hour fuel moisture in the East Idaho Highlands (including Island Park) is 12.53%
• 100-hour fuel moisture in the Snake River Valley is 9.72%.

We are on the same track as we were in 1988.

Contrary to popular belief, a fire truck will not be sitting in your driveway to protect your home in the event of a wildland fire. It is the property owner’s responsibility to reduce the risk of wildfire for their property

To learn how to protect your home from wildland fires visit: https://www.nfpa.org/en/education-and-research/wildfire/preparing-homes-for-wildfire

249 PM MDT Tue May 26 2026..STRONG THUNDERSTORMS WILL IMPACT TETON...SOUTHEASTERN FREMONT...NORTHEASTERN BONNEVILLE AND ...
05/26/2026

249 PM MDT Tue May 26 2026
..STRONG THUNDERSTORMS WILL IMPACT TETON...SOUTHEASTERN FREMONT...
NORTHEASTERN BONNEVILLE AND EASTERN MADISON COUNTIES THROUGH 315 PM
MDT...

At 248 PM MDT, Doppler radar was tracking a cluster of strong thunderstorms over Tetonia, or near Driggs, moving northwest at 30 mph.

HAZARD...Wind gusts in excess of 45 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around unsecured objects. Minor hail damage to outdoor objects is
possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Address

151 West 1st North
Saint Anthony, ID

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