Researchers recorded a high of 69.35 on an island off the coast of the continent, which they described as "incredible and abnormal."
“We are seeing the warming trend in many of the sites we are monitoring, but we have never seen anything like this,” said Brazilian scientist Carlos Schaefer, according to the BBC.
It was nearly two degrees higher than the previous record of 67.64 degrees set 37 years ago.
The reading was taken at a monitoring station on Seymour Island, which is part of a chain of the islands on the Antarctica Peninsula -- the northernmost part of the continent.
Schaefer said the reading was a single data point, so they're not able to determine if it's a trend that will continue in the future.
"We can't use this to anticipate climatic changes in the future. It's a data point," Schaefer said, according to the television network. "It's simply a signal that something different is happening in that area."
Antarctica also experienced record heat last week, recording a temperature of nearly 65 degrees on the continent's northernmost peninsula.
Scientists at Terrantar, a government project that monitors climate change on the continent, said the record temperatures are most likely attributed to changes in ocean currents.
“We have climatic changes in the atmosphere, which is closely related to changes in permafrost and the ocean," they said, according to the Guardian.