Officials have said they did not expect the explosion to be deadly as long as people remained out of the park. It looked like it was a steam and ash plume.
"At any time, activity may again become more explosive, increasing the intensity of ash production and producing ballistic projectiles near the vent", it said in a statement.
"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".
"We may have additional larger, powerful events", US Geological Survey geologist Michelle Coombs told a news conference in Hilo.
Hawaii's emergency management agency advised people in the area affected by ash to stay in their homes if possible.
"They said they slept through it".
Kanani Aton, a spokeswoman for Hawaii County Civil Defence, said she spoke to several relatives and friends in the town called Volcano.
So, the national park has been closed since last week.
Thursday's eruption, which occurred before dawn, produced an impressive ash plume, but otherwise caused minimal damage to surrounding areas.
"The one this morning is definitely the biggest we've seen so far, just in terms of energy and how high up into the atmosphere it got".
Some people in the community closest to the volcano slept through the explosion.
In the intervening time, stormy weather is reason of the ash to mix with rain, creating a dark paste that coated rooftops and vehicle windshields.
In the Hawaii Volcano Observatory, a webcam caught the consequences of the short-lived eruption: an onslaught of wet, dusty ash raining on a darkened landscape.
GETTYThe Hawaii volcano erupted this morning
"It was a grit, like a sand at the beach", said Joe Laceby, who lives in the town of Volcano a few miles to the north-east of Kilauea's summit.
"Our shelters are set up so we're not downwind from where the gasses are", he said. This type of eruption has the potential to carpet the Big Island in much thicker ash than current dustings.
"And it is not likely to turn into some catastrophic event", he added.
"Tall but small", she said of Thursday's plume. Eruptions are expected to continue over the coming days.
The worldwide airports in Hilo and Kona are open, officials said.
This increases the risk of steam-powered explosions as the magma meets underground water.
Kīlauea has erupted in this manner before.
Kilauea has erupted in this manner before, in the May of 1924, the Hawaii Volcano Observatory reported more than 50 explosive events more than the course of two-and-a-half weeks at the volcano's summit.
Continuous ash emissions from Halemaumau crater are reaching as high as 12,000 feet.
At least one person who was awake heard nothing. On the other hand, stratovolcanoes - which include Mount Pinatubo in the Philippines and Mount St. Helens in Washington State - are usually taller and have more viscous lava flows with trapped gas that can generate volatile explosions.
What is happening at Kīlauea is fundamentally different from that 1980 eruption, experts said.
This is because Kilauea is a so-called shield volcano, which is typically broader in shape and has lava that is relatively fluid. He explained from time to time he can feel the rumblings from the active volcano.