Lava illuminates volcanic gases from the Kilauea volcano at fissure 13 on Hawaii's Big Island on May 16, 2018 in Pahoa, Hawaii.
In a news conference, scientist Michelle Coombs of the US Geological Survey said the activity could become explosive again.
"It's just time to go - it really, really is", she said, preparing to leave town.
Halemaumau is the crater within Kilauea's summit caldera.
"I think it's going to be a series of explosions similar to the one that happened this morning, and that's based on what happened in 1924, which is really our only analog", he said of the almost century old event, which lasted 2-1/2 weeks and killed one person who was hit by a "ballistic block".
The volcano.it's a real dynamic situation up there. we could have additional events like this morning that punch up and then die back down really quickly. we could have more sustained ash.
As people could be seen, in the distance, standing in amazement as the ash plumes rose into the sky from the Kilauea volcano, a couple of golfers were pictured mid-round at the Volcano Golf & Country Club, located within Volcanoes National Park.
The eruption occurred shortly after 4 a.m. local time, the Hawaii County Civil Defense Agency said.
TI arrested outside of his gated community
Media reports say the rapper, whose real name is Clifford Harris, lost his key and the guard wouldn't let him into the community. His attorney insists that he was wrongfully arrested after returning to the Eagle's Landing Country Club community around 4 a.m.
Observatory staff had left their Kīlauea station Wednesday, for a facility at the University of Hawaii at Hilo, after concluding that wind could carry ashfall their way. "Impacts will be limited to an area around Halemaumau".
That's where the explosion would have sent hot gas and 1,000-pound (450 kg) rocks soaring.
Residents who live in a nearby town reported light amounts of ash after the eruption.
Scientists warned on May 9 that a drop in the lava lake at the summit might create conditions for an explosion that could fling ash and boulders the size of fridges into the air.
Today's eruption prompted a shelter in place warning, residents were told to keep their windows closed and be prepared for ash fall and even small rock fragments.
Linda Ugalde, a 20-year resident of Volcano, said she heard and felt nothing, but stepped outside of her home at the Volcano Golf Course subdivision about 10 minutes after the alert to find a film of dark gray ash coating the railing on her lanai and the plants in her garden and yard.
Some people in the community closest to the volcano slept through the explosion.
Meanwhile, stormy weather caused the ash to mix with rain, creating a dark paste that coated rooftops and auto windshields.