This is the warmest September on record for Denver.
Sunday's 90-degree heat sealed the deal.
"Cooler temperatures that will move in Monday and Tuesday aren’t cool enough to change that," said Storm Station 7 Meteorologist Matt Makens.
The average monthly temperature this year is about 69.7 degrees, according to the National Weather Service in Boulder. The previous record was 68.3 degrees - set in 1948.
This September is currently the fourth driest on record, Makens said.
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