What volcanoes are active in the US?

Active Volcanoes in the US: A Comprehensive Overview (Humanized Version)

Did you know the United States is sitting on a whole lot of potential volcanic action? Seriously, we’re talking about roughly 169 active volcanoes, most of them chilling (or not so much) up in Alaska. That’s a lot of geological firepower! Thankfully, the USGS – those awesome folks at the United States Geological Survey – keeps a close eye on these fiery mountains. They’re working hard to predict eruptions and keep communities out of harm’s way.

So, what exactly does “active” mean when we’re talking about volcanoes? Well, it’s not like they have a 9-to-5 job. The Smithsonian Institution’s Global Volcanism Program (GVP) has a pretty long view on things. They consider a volcano active if it’s blown its top sometime in the last 11,700 years. That might seem like a while, but in geological terms, it’s practically yesterday! This long-term perspective is super important for understanding what these volcanoes might do in the future.

Where are these volcanoes lurking? As I mentioned, Alaska is the hot spot (pun intended!). But you’ll also find them in Hawaii, and scattered throughout the western states – Washington, Oregon, and California. They’re all part of the Pacific Ring of Fire, that notorious zone of earthquakes and volcanoes that encircles the Pacific Ocean. It’s a pretty active neighborhood, geologically speaking.

What’s happening right now? Well, as of August 6, 2025, the Global Volcanism Program was tracking 46 volcanoes worldwide that are currently erupting. A “continuing” eruption means the volcano’s been acting up on and off for at least three months straight.

Let’s zoom in on a few of the more notable ones here in the US:

• Kīlauea, Hawaii: This one’s a real rock star – one of the most active volcanoes on the planet! It’s been putting on a show within its summit caldera since late December 2024. In fact, just recently, on August 6, 2025, Episode 30 of the eruption inside Halemaʻumaʻu Crater wrapped up after a solid 12 hours of lava fountains. And get this – a brand-new fissure vent even opened up on the south wall of the crater! The USGS Hawaiian Volcano Observatory (HVO) is all over it, of course. They’re seeing signs that another episode might be brewing soon.
• Great Sitkin, Alaska: Over in the Aleutian Islands, Great Sitkin has been erupting steadily since July 2021. It’s not a flashy eruption, just slow and steady lava flowing into the summit crater. There are occasional small earthquakes and rockfalls, too, just to keep things interesting.
• Mount Spurr, Alaska: Spurr isn’t erupting right now, but it’s still on “Advisory” status, which means it’s showing some signs of unrest. There are little earthquakes happening under the volcano from time to time. The Alaska Volcano Observatory (AVO) says an eruption is possible, but not super likely at the moment. Still, they’re watching closely.

And then there are the volcanoes that are a little quieter right now, but still worth keeping an eye on:

• Mount St. Helens, Washington: Ah, St. Helens. Most of us remember the big eruption in 1980. It’s still considered active, though. It last erupted between 2004 and 2008, and it’s still a high-threat volcano.
• Mount Rainier, Washington: This one’s a beauty, but also a bit of a worry. It’s covered in ice, and if it were to erupt, all that ice could melt and cause massive mudflows (called lahars) that could be devastating.
• Mauna Loa, Hawaii: The biggest volcano on Earth, by volume! It erupted in late 2022, which was a pretty big deal. The Hawaiian Volcano Observatory is keeping a close watch on it.
• Mount Redoubt, Alaska: This one last blew its top in 2009, and it caused a lot of problems for air travel.
• Lassen Peak, California: Lassen had a series of eruptions way back in the early 1900s (1914-1921), and it’s still considered active.

So, how do we keep track of all this volcanic activity? The USGS has five volcano observatories that are constantly monitoring things. They use all sorts of fancy equipment – seismometers to measure earthquakes, GPS to track ground movement, and gas sensors to sniff out changes in the gases coming from the volcanoes. All this data helps them figure out what’s going on and give us warnings if something’s about to happen.

The bottom line? The US is a pretty volcanic place. While eruptions can be dangerous, scientists are working hard to understand these volcanoes and keep us safe. It’s a fascinating and important field of study, and it’s something we all should be aware of, especially if you live near one of these amazing (and potentially explosive) mountains!