World's tallest geyser may erupt at Yellowstone National Park

YELLOWSTONE NATIONAL PARK, Wyo. -- Yellowstone National Park has reported a series of potential eruptions from the world's largest active geyser for the first time since 2014. Park officials said employees reported seeing an eruption at the Steamboat Geyser in northwest Wyoming Thursday evening.

Geologists comparing the eyewitness reports to remote thermal sensors believe the activity could be a series of minor eruptions.

Steamboat Geyser, in Yellowstone National Park's Norris Geyser Basin in Wyoming, erupts on Wednesday, July 31, 2013. Robb Long / AP

Steamboat is located in a part of the park that's snowed in much of the year. Roads into the area currently are closed for spring plowing.

Geysers are constricted hot springs that erupt as the water heats up. Steamboat's major eruptions can shoot steam to heights of 300 to 400 feet.

By comparison, steam from Yellowstone's world-renowned Old Faithful Geyser, which erupts like clockwork more than a dozen times daily, averages 130 feet in height.