Monsoons - from thunderclouds to rainbows
Monsoon season is in full swing for us in the Valley of the Sun.
The North American monsoon occurs from late June or early July into September, originating over Mexico and spreading into the southwest United States by mid July. It affects Mexico along the Sierra Madre Occidental as well as Arizona, New Mexico, Utah, Colorado, West Texas and southern California. The North American monsoon is known as the Summer, Southwest, Mexican or Arizona monsoon.
Most days now we see tall, dark puffy clouds forming during our hot humid afternoons. These cumulonimbus clouds are often nicknamed "thunderheads". They can form any time of the day when the temperatures fall rapidly higher up in the sky. These tall dark clouds are full of moisture and contain strong up and down air currents. Cumulonimbus clouds may tower more than 50,000 feet and cover from just a few square miles up to two hundred square miles.
Although the monsoon brings welcome rains and relief from the summer heat, the thunderstorms that come with the monsoon bring their own hazards. In fact, this is the most dangerous time of year in The Valley.
I both love and hate monsoon time.
I love the cloud formations which are amazing!!! The clouds look like cotton candy. I'm sure we have all looked at clouds and said, "Wow, that looks like a fish, a face, Mickey Mouse or a dinosaur". We have all played that game one time or another.
At times, I love to watch lightning which can last for hours. There is nothing more unique than watching huge lightning bolts splinter off in so many directions and hit the ground; or to watch the lightning dance between clouds that stretch on for miles. I enjoy looking at all the lightning across The Valley but not when it is crackling above the house.
Our house is located in McDowell Mountain Ranch in the 100 Hills subdivision. Yes, it seems like there are a hundred little hills behind the house. During a storm, thunder can bounce off the hills and echo on and on and on and on....
The rains the monsoon produces are a welcome relief to the desert. The desert only needs a little amount of rain in order for it to green up. The rains may come down in sheets, as a sprinkle or as a blinding downpour.
Unfortunately, flash floods are the #1 thunderstorm related killer. Along roadways there are many low water crossings and dips which quickly flood during a rain. Drivers should know where they are and avoid these areas during heavy rains. If you find yourself in a situation where flash flooding is occurring, get to higher ground. Never drive into a flooded roadway. The water depth is very easy to misjudge and the road itself may be damaged or destroyed underneath the murky water. Be extra cautious at night. Fast moving water 1 to 2 feet deep will carry away most vehicles. Never drive around barricades. There are reasons the barricades are there - usually because flash flooding is about to take place, is happening or the road is damaged by flooding and it is unsafe. You should find an alternate route, be patient or wait for the flooding to subside.
Six inches of fast moving flood waters can kick you off your feet and a depth of two feet will float your vehicle. Never try to walk, swim or drive through swift running water. Never play near washes or storm drains after any rainfall, no matter how light. These flood easily and rapidly and storm drains are usually so large that children can be swept away.
You should also be aware of distant thunderstorms, especially if they are over mountains. Flash flooding can occur many miles from the thunderstorm as the runoff flows into arroyos, washes and streams.
During a monsoon, do not camp or park your vehicle near streams and washes. Although many of the thunderstorms occur during the afternoon and evening, some of the worst flash floods have happened in the middle of the night. Hikers and mountain bikers should try to leave flood areas earlier in the day to avoid the dangers of not only flash flooding but lightning. If you are hiking during the monsoon, be to ready to move, be aware of your escape routes, follow ranger instructions and/or be prepared to move to higher ground quickly.
Dust storms are another danger. A dust storm, or Haboob, usually arrives suddenly in the form of an advancing wall of dust and debris which may be miles long and several thousand feet high. The dust storm arrives with little warning. This makes driving conditions hazardous. Blinding dust can quickly reduce visibility. The storms, however, usually last only a few minutes. The actions a driver takes are very important.
If a dense dust is seen blowing across or approaching a roadway, pull your vehicle off the pavement as far as possible, stop, turn off lights, set the emergency brake and take your foot off the brake pedal to be sure the tail lights are not illuminated. Make sure all the vehicle lights are off.
Unlike other parts of the country, thunderstorm wind gusts in the Southwest almost always exceeds 40 mph. The strongest wind gusts can exceed 100 mph and can produce damage similar to a tornado.
Anytime a thunderstorm approaches, no matter how weak it seems, move indoors to avoid flying debris. Winds rushing down from a thunderstorm can develop very quickly.
These sound like common sense things to do but you will be surprised how many people don't follow the simple rules.
There have been many monsoon tragedies this summer. Reportedly water up to 6 feet high and 40 feet wide swept away 14 members of a family, carrying them fast and far downstream. Ten of them including five children ages 2 to 13 died in the flash flood. Heavy rain was falling eight miles upstream from where they played in the Cold Springs swimming hole in the Tonto National Forest. The stretch of river is known for canyons and water channels. The sky was clear above them. Summer fires had cleared ridges and slopes of vegetation, so there was nothing to slow the tremendous volume of water that swept down on them so very quickly. They had no warning. They heard a roar and the water was on top of them.
The monsoon storm that hit The Valley on August 3rd forced the Phoenix Zoo to close. Luckily, all the animals were safe and accounted for. However, there were multiple trees down. Two tents were destroyed. Flooding left debris on several of the zoo trails.
This week, when Michael was flying to Denver, the pilot tried to beat the Haboob. Luckily, the plane just got above it in time. The plane only went sideways for a few seconds.
After a thunderstorm, you may be treated to a beautiful rainbow.
We experience beautiful sunsets all year but I like this time of year when we get beautiful rainbows, too.
The mountains behind our house provide a beautiful backdrop.