
What is an Arizona Monsoon?
The Arizona Monsoon is a weather pattern that occurs every summer in the Southwest, including Arizona.
This season is characterized by an increase in moisture, which results in thunderstorms and heavy rainfall.
The monsoon season typically lasts from mid-June to the end of September, with peak storm activity occurring in July and August.
The monsoon season is caused by a shift in wind patterns, which brings moisture from the Gulf of Mexico and the Pacific Ocean into the region.
This moisture combines with the intense heat of the Sonoran Desert to create the perfect conditions for thunderstorms.
The National Weather Service defines a monsoon as a weather pattern that brings at least three consecutive days of thunderstorms and a 40% increase in moisture.
Monsoon storms can range from minor dust storms to severe thunderstorms, with lightning strikes, hail, and heavy rainfall.
Microbursts, which are intense winds that spread out in all directions, can also occur during monsoon storms and cause damage.
The storms often begin with haboobs, walls of dust that can be hundreds of feet high and bring high winds.
The Arizona Monsoon has a significant impact on the state’s annual precipitation, with up to 50% of the annual rainfall occurring during this season.
The wettest monsoon in Phoenix was in 1984, with 9.56 inches of rain recorded at Phoenix Sky Harbor International Airport.
In contrast, the driest monsoon was in 1924, with only 0.35 of an inch of rainfall recorded.
What is a Haboob?
A haboob is a type of dust storm that is characterized by a massive wall of dust created by strong winds that flow downward and outward as they exit a collapsing thunderstorm.
These storms generally last for a couple of hours and can blow from any direction.
Haboobs are more common in the summer months and are found in desert regions all over the world, including the Middle East.
They are also known as “arabic word” and “blowing dust” storms.
Haboobs are dangerous dust storms that can cause damage to property and pose a risk to human health.
When is Arizona’s Monsoon Season?
If you’re planning to visit Arizona during the monsoon season, you’ll want to know when it officially begins and ends.
Prior to 2008, the monsoon season’s start date and duration varied based on the dew point average.
However, to reduce confusion, the National Weather Service decided to set dates. Now, the season officially begins on June 15 and ends on September 30.
It’s worth noting that these dates coincide with great Arizona Staycation rates and Chandler hotel deals for summer.
If you were to use the dew point method, the monsoon would usually start around July 7 on average and conclude approximately two months later, soon after Labor Day.
What You Need to Know About Visibility
When driving in monsoon storms, visibility can quickly become a major issue due to dust and heavy rains.
If you see a wall of wind approaching, it is crucial to get to a safe place as soon as possible.
This may mean going directly home or to your hotel, or pulling into a parking lot and waiting out the storm.
If your visibility suddenly reduces due to dust or heavy rains, slow down and keep driving straight.
Avoid making unnecessary lane changes.
If you feel like conditions are too dangerous to continue driving, slowly pull off the side of the road as far right as possible, turn off your car and lights, and keep your foot off the brake pedal.
This will prevent other drivers from rear-ending your vehicle.
It is important to note that high winds can also affect visibility, especially if they are strong enough to make your car shake or affect your windshield wipers.
In these cases, it is recommended to pull over and wait until the winds die down before continuing your journey.
Do Monsoons Cause Flooding?
Monsoons are known for bringing heavy rains to the Valley, which can lead to flash floods and flooding.
The intense rainfall during monsoons can cause washes to quickly fill up, and entire streets can even flood.

The dry ground in the Valley has a difficult time absorbing the rainfall, which can exacerbate the flooding.
It is important to never underestimate the power of flowing water during monsoons.
Even a small amount of water can be much deeper than it appears, and as little as 6 inches of water can sweep a person off their feet.
A depth of 24 inches can even wash a car off the road. Even high-clearance vehicles are at risk in just 24 inches of water.
If you come across an area with running water, it is important to never attempt to cross it, especially if a nearby sign warns against crossing when flooded.
The “Stupid Motorist Law” in Arizona allows municipalities and rescue agencies to charge individuals for the cost of being rescued if they fail to observe posted warnings.
Your miscalculation can cost you not only financially but also your life.
In the event that there are no signs posted and you stall in a wash or other flooded area, try to climb onto the roof of your car and call 911 using your cell phone.
Rescue workers will come to your aid as soon as possible.
It is important to remember that monsoons can cause flash floods and flooding, and to always exercise caution around running water during this time.
What to Do During a Monsoon
Monsoons can be dangerous, so it’s important to take precautions to ensure your safety. Here are some tips to keep in mind during a monsoon:
- Stay indoors if possible.
If you don’t need to go outside, it’s best to stay indoors during a monsoon. This will help keep you safe from lightning strikes and flying debris. - If you must go outside, be cautious.
If you need to go outside during a monsoon, be sure to drive cautiously and avoid areas with standing water.
Remember that roads can be slick due to oils and other automotive fluids, so it’s important to drive slowly and carefully. - Stay away from tall objects.
During a monsoon, it’s important to stay away from open fields, high land, trees, poles, and other tall objects to avoid being struck by lightning. - Avoid plumbing fixtures.
Lightning can travel through metal pipes, so it’s important to avoid plumbing fixtures like showers, baths, and sinks during a monsoon. - Keep your distance from windows.
Windows can be struck by blowing debris, including trees, during a monsoon.
To avoid injury from flying glass, it’s important to keep your distance from windows.
Remember to always be prepared for a monsoon by having a plan in case of a power outage or other emergency.
And if you do need help, be sure to contact local rescue agencies for assistance.
By following these tips, you can stay safe during a monsoon and avoid any potential dangers.