A 40-feet deep hole that emerged in the backyard of a Florida woman's home one day after a pool party sucked her pool dry and led her to evacuate the premises.

Suzanne Blumenauer arrived to her home near Winter Park Monday night to see her backyard pool empty and sinking into the ground. Blumenauer called authorities who initially thought the 50-foot wide mass was a sinkhole but are now not sure what it is.

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"We don't even know if it is a sinkhole," Robert Amato, Orange County building inspector, told the Orlando Sentinel. "It doesn't look like it moved since yesterday."

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Blumenauer, who could not be reached today by ABCNews.com, voluntarily left her home until authorities can confirm it is safe for her to move back in. The hole is 20 feet from her back door, the Sentinel reports.

Blumenauer threw a pool party at her home Sunday night but says nothing was amiss until she returned from dinner on Monday and noticed the hole while on the phone with a friend.

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"I said, 'Karen, I have a sinkhole in the back yard,'" Blumenauer told ABC affiliate WFTV. "I think I might be dreaming. I didn't know what to think, [and] then I realized there's a hole in the ground."

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Officials are back on the scene at Blumenauer's home today further inspecting the hole. Calls placed today by ABCNews.com to the Orange County building inspector's office and fire department were not returned as of this writing.