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Wednesday marks the last day of 2020’s underwhelming monsoon season, with no rain in sight for the foreseeable future.

“If it’s not the driest, it’s one of the driest on record,” said National Weather Service meteorologist Marvin Percha, who is still tabulating the final statewide numbers.

Phoenix Sky Harbor Airport received only an inch of rainfall and only two days of measurable rain since June, Percha said, the 12th lowest amount in recorded history. However, he added, most locations around the Phoenix area fell short of even that.

A data map from the Flood Control District of Maricopa County comparing this season’s rainfall totals for areas throughout the county to totals measured in 2018 and 2019 shows a dramatic drop in moisture levels Valley-wide.

Few areas across the entire county surpassed 1 inch of rain in 2020’s monsoon, even areas to the east that measured 4 to 5 inches in 2018 and 2019. Several places in central Phoenix received less than a tenth of an inch this year after getting 2 to 3 inches in the two years prior.

Meanwhile, Flagstaff reported its driest monsoon season since records began in 1898, registering less than 2 inches of precipitation, according to a graphic shared by the National Weather Service office there. Flagstaff’s average total by this time of year is more than 8 inches.

Other locations in northeast Arizona also saw their driest summer in recorded history, including Prescott, the Grand Canyon Airport and Window Rock.

This year’s “nonsoon” season is due to a high pressure system from the south that persisted over the Southwest United States, Percha explained. Usually, this high pressure moves through Arizona and continues north, pulling moisture northward from Mexico.

“As a result, we ended up with an extremely hot and dry summer as the high pressure provided the heat and suppressed most of the moisture and thunderstorm activity,” Percha said.

Unlike the consistently record-breaking high temperatures this summer, which follow an upward trend in the last several decades due to human-caused climate change, there is no indication that things are trending drier over time, Percha continued.

“If there is a longer term signal, the jury is still very much out on that one,” he said.

No rain is expected in the Phoenix area at least for the next two weeks, according to the National Weather Service. Temperatures will continue to be above normal until the weekend, when the weather is fortunately forecast to cool.

Reach the reporter at [email protected] or on Twitter @vv1lder.

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