What exactly is an Arizona monsoon?

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If you're unfamiliar with a monsoon, there is plenty to expect. (Source: 3TV/CBS 5) If you're unfamiliar with a monsoon, there is plenty to expect. (Source: 3TV/CBS 5)
Blinding walls of dust! (Source: 3TV/CBS 5) Blinding walls of dust! (Source: 3TV/CBS 5)
Torrential downpours turning roads into rivers! (Source: 3TV/CBS 5) Torrential downpours turning roads into rivers! (Source: 3TV/CBS 5)
Just like popcorn, storms burst without warning. (Source: 3TV/CBS 5) Just like popcorn, storms burst without warning. (Source: 3TV/CBS 5)
On average, the monsoon in Phoenix produces just under 3 inches of rain, which is about a third of the total rain for an entire year. (Source: 3TV/CBS 5) On average, the monsoon in Phoenix produces just under 3 inches of rain, which is about a third of the total rain for an entire year. (Source: 3TV/CBS 5)
PHOENIX (3TV/CBS 5) -

Last Friday marked the official start of the monsoon season and rain quickly followed suit in the Phoenix area.

But what exactly does it mean to begin the monsoon season?

If you're unfamiliar with a monsoon, there is plenty to expect.

[RELATED: Monsoon rolls into the state with a stormy Saturday]

Blinding walls of dust! 

Torrential downpours turning roads into rivers!

Powerful winds knocking down trees, snapping power lines and capsizing boats!

Even rare tornadoes! 

This is only some of the things an Arizona monsoon can bring.

Scientists designated June 15 as the official start of the season and the end coming on Sept. 30. However, the monsoon doesn't truly kick into gear until we get three consecutive days of dewpoints at around 55 degrees or higher.

[SLIDESHOW: Saturday monsoon rolls into town]

During the monsoon, thunderstorms spawn from a moisture supply that pumps into our atmosphere from the Gulf of Mexico and the Gulf of California.

The air will feel sticky, and with daytime heating, towering cumulus clouds build.

Just like popcorn, storms burst without warning.

Early in the season, outflow winds from thunderstorms south of the Valley will blow over open desert, turning the sky brown with dust.

[RELATED: The monsoon can have unwelcome effects on your health]

Shortly after, the first rain for the summer falls over the parched land. But instead of being absorbed into the ground, dry washes fill and flash flooding becomes a common danger.

On average, the monsoon in Phoenix produces just under 3 inches of rain, which is about a third of the total rain for an entire year.

The Mogollon Rim, White Mountains and Kaibab Plateau will get much more.

[SPECIAL SECTION: Arizona Monsoon 2018]

These storms are important to help fight wildfires and provide vital water to the wildlife.

The monsoon also brings out a wide array of critters from scorpions to snakes.

Searing temperatures - peaking around 120 degrees in Phoenix by late June - will give way to the 80s after a cooling thunderstorm in mid-July.

Relief from the relentless summer heat. But as history shows, the monsoon is also a catalyst for destruction.

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Copyright 2018 KPHO/KTVK (KPHO Broadcasting Corporation). All rights reserved.


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