The Verde Valley has experienced the first monsoon storms of the season.
For those new to the Verde Valley, the Arizona monsoon is a weather pattern, similar to but less intense than the Indian monsoon in Asia. Under intense summer heat in the Sonoran Desert and the Mexican plateau, winds shift and a low pressure thermal flow forms, pulling moisture from the Gulf of Mexico and the Sea of Cortez.
The result is massive summer storm clouds that roll into Arizona’s skies, dumping loads of rain as they collide with each other, high-pressure areas or temperature differentials, such as between the Verde Valley and the Mogollon Rim.
On a practical level, it means we’re looking at big storms and intense mircobursts that drench portions of the area quickly and without warning.
Expect low areas to endure flash floods. Be careful driving through dry washes. Keep in mind that they were crafted by Mother Nature after centuries of annual monsoons. Do not park nor camp nor hike through washes if storms are expected. A sudden monsoon storm can hit with little notice and turn those washes into raging torrents.
Do not try crossing a wash in a flash flood. The surface water make look like it’s moving slowly, but just beneath the surface, water can be moving twice as fast. And washes may look shallower than they are.
If you ignore signage, try to cross and you get stuck, requiring emergency crews to rescue you, Arizona Revised Statute §28-910, aka the “stupid motorist law” means you can be billed for the cost of your own rescue by the agencies doing the rescue, plus an additional $2,000. Don’t cross a wash — find another way around.
All the towns and cities in the Verde Valley have been working on flood mitigation projects over the last few years, but these only work properly if those upstream keep potential waterways clean.
If you have washes, culverts or drainage ditches on your property, make sure they are cleaned of debris. If water can’t flow downhill, it can cause flooding. One example of this was a September 2009 mircoburst at Tlaquepaque. Debris clogged the ditch that led into Oak Creek. Water flooded the shopping plaza’s parking lots, sweeping three cars into the ditch, blocking it even more, causing several inches of mud and debris that was headed downstream to instead sweep into the arts and crafts village, causing tens of thousands of dollars in damage to cars and the property.
Just because rains are here, fire danger doesn’t go away either. A few days of heavy rain may quench the desert, but a week of hot, dry whether thereafter dries it out, returning the area to high-risk fire danger.
If you are uncertain about fire conditions, contact your local fire department or district and ask.
Stay safe and enjoy the summer monsoon. The skies are gorgeous as huge, high clouds billow into the blue and catch the setting sun. Remember they can be dangerous, but if you stay alert, the monsoon is one of the best natural wonders to enjoy while living in Arizona.