It’s July in the Sonoran Desert, which means monsoon season is in full swing. This seasonal change in the weather pattern sends most desert dwellers outside in the late afternoon, casting eager glances skyward in the hope of finding rain-laden thunderheads blooming on the horizon. In a state that gets only seven inches of rain per year (on average), the slightest hint of precipitation is welcomed with open arms and actual raindrops leave us downright giddy. To celebrate our annual “Monsoon Madness,” here are some interesting facts to ponder:

  • Arizona’s monsoon season begins when intense solar heating causes the air over the desert to rise. This creates low pressure near the ground that pulls up moist air from the Gulf of Mexico, temporarily changing our weather pattern. 
  • The meteorological rule of thumb is that three consecutive days with an average dew point of 55 degrees Fahrenheit or higher marks the official arrival of the monsoon season.
  • Monsoon season typically runs from early July to mid-September. 
  • A hearty monsoon-driven thunderstorm can temporarily cool the air temperature by 20 degrees or more in a matter of minutes. 
  • Dust storms, also called haboobs, often precede desert thunderstorms. Heavy winds blowing over fields and the open desert can generate enormous clouds of dust. The average wind speed of a haboob is more than 30 miles per hour and the wall of dust can reach 3,000 feet in height. Though they only last a few minutes, dust storms can quickly reduce visibility, which is particularly hazardous if you are driving (click here for dust storm safety tips).
  • Summer thunderstorms can drop more than an inch of rain in a very short period of time. Watch out for localized flooding and never try to walk or drive across a flowing wash.
  • If you’re lucky enough to be in Scottsdale and near the desert on one of our rare rainy days, step outside when the rain stops and take a deep sniff. The delightful fresh fragrance in the air is emitted by creosote bushes when their leaves get wet.

Enjoy this great footage!