Is our monsoon changing?

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Some intense storms have flooded freeways in the Valley. (Source: 3TV/CBS 5) Some intense storms have flooded freeways in the Valley. (Source: 3TV/CBS 5)
This photo was taken on July 18, 2016. (Source: Jerry Ferguson) This photo was taken on July 18, 2016. (Source: Jerry Ferguson)
(3TV/CBS 5) -

Is our monsoon season changing? A new study from the University of Arizona researchers seems to indicate that it is. And that’s not good news for Valley residents. 

Monsoon season, which runs from June 15 through September 30 in Arizona, brings some of our biggest weather threats. Flash flooding, strong winds including microbursts and dust storms are pretty common during this season. 

[Special section: Arizona monsoon 2017]

In this recent study, researchers found that while we aren’t having MORE storms, the storms we are having are more intense. That means stronger winds and heavier rain, which equates to more loss of property and life. The researchers compared weather data from 1950-1970 to data between 1991-2010.  They found that the regions seeing more intense storms include Kingman, Yuma, Casa Grande and the Phoenix Metro area.

[SLIDESHOW: Best of Arizona's 2017 monsoon]

MOBILE/APP USERS: Click here to see the image of monsoon storms in the Valley

[SPECIAL SECTION: Weather blog]

Researchers believe this is the result of climate change and is consistent with what they expect throughout the world due to climate change. While rainfall amounts during monsoon season didn’t change much over the last 60 years, there were fewer, but more intense storms producing those totals. And the more intense storms that produced that heavy rain also brought stronger winds, including more frequent microbursts.

[RELATED: Phoenix Rainfall Index looks at the big rain picture]

MOBILE/APP USERS:  Click here to see the pic of a microburst over Phoenix

This is one of the first studies to look at long-term changes in the monsoon. This same research team in the University of Arizona’s Hydrology and Atmospheric Sciences department plans to next look at how the North American monsoon may be changing in Mexico. 

[RELATED: The magnificent microburst]

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