(CNN) Summer is only a month old, but one record has already been smashed. Average thermometer readings around the globe reached previously unseen highs, making June 2019 the hottest June on record, according to new data from the National Oceanic and Atmospheric Administration.

Scorching temperatures also brought Antarctic sea-ice coverage to a new low for the second month in a row, the administration said.

Second warmest year to date

The 20th-century average thermometer reading for June was 59.9 degrees Fahrenheit, yet global temperatures in June 2019 averaged 1.71 degrees above that, according to scientists at NOAA's National Centers for Environmental Information. In 140 years of recording temperatures, that's the hottest June scientists have witnessed.

Though a new record, it comes as no surprise to those who watch the weather: Nine of the 10 hottest Junes have occurred since 2010. In fact, last month was the 43rd consecutive June that rose above averages of the past.

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