Each of the 48 contiguous states came in above its average temperature for June, with Arizona and Utah setting all-time June records for heat. Thirteen other states had a top-ten-warmest June, stretching across the nation from California to Florida.

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In line with a global climate that’s being warmed by greenhouse gases, the contiguous United States has seen six of its ten warmest summers on record in just the last 15 years. On that basis alone, 2016 has a reasonable shot at becoming our hottest summer yet, especially with the head start provided by a record-warm June. On the other hand, there is plenty of inherent variability from week to week and month to month, even in weather that’s averaged across the country