AP Photo/Chicago Tribune, Zbigniew Bzdak

AP Photo/Chicago Tribune, Zbigniew Bzdak

Blink and you missed your chance to visit the Apostle Islands Ice Caves this year.

Visitors have until 7 p.m. Monday evening to visit the icicle-encrusted caves along the Lake Superior shoreline in northern Wisconsin. There are gale-force winds in the forecast, followed by temperatures in the 40s and 50s, forcing officials at the Apostle Islands National Lakeshore to close the ice caves for the season.

"It was a short but sweet ice cave season -- thanks for coming!" park officials announced on their Facebook page. The high winds and warmer weather greatly increase the instability of the ice underfoot, as well as the massive ice formations dangling over visitors' heads.

In the nine days the caves were open and accessible to visitors this season, 36,000 people trekked across the slippery surface of Lake Superior to marvel at the glittering caves. This weekend alone, the park service saw 17,000 visitors. 

"This has been an amazing boon to the regional economy and although we would love this to continue for another month, the safety of the visitor always comes first," Bayfield Chamber of Commerce and Visitor Bureau Executive Director David Eades said in a statement.

Last winter, 138,000 visitors flocked to the caves near Cornucopia, Wis., over the course of 10 weeks. The frigid polar vortex made the caves accessible for the first time in five years and news of their beauty went viral on social media.

AP Photo/Chicago Tribune, Zbigniew Bzdak

AP Photo/Chicago Tribune, Zbigniew Bzdak