"A monsoon ... in ARIZONA? Surely you jest!?
Yes, indeed! Contrary to the denials of Arizona old-timers, we here in the Southwest do have a "monsoon."
How can Arizona, a desert, have a monsoon like India?
Actually one of the reasons that India has its more famous monsoon is largely due to the huge Rajasthan Desert in western India. But more fundamentally a 'Monsoon' is linked more to a wind shift rather than precipitation. In fact, the name "monsoon" is derived from the Arabic word "mausim" which means "season" or "wind-shift". Again, for India, during the winter dry period, the airflow comes from high pressure to the norththe dry Himalayas and Siberia. For the summer, the desert of western India heats up and low pressure forms. This causes air to swirl in from the west, the south and the eastall oceans! The result? HEAVY RAIN!
The Arizona Monsoon is a well-defined meteorological event (technically called a meteorological 'singularity') that occurs during the summer throughout the southwest portion of North America. During the winter time, the primary wind flow in Arizona is from the west or northwestfrom California and Nevada. As we move into the summer, the winds shift to a southerly or southeasterly direction. Moisture streams northward from the Pacific Ocean and the Gulf of Mexico. This shift produces a radical change in moisture conditions statewide."
so now I'm very jealous. I love a good storm! In the UK we've been having awkward rain storms. It's chucking it down now but in the next hour it'll be blisteringly hot and not a cloud in the sky. You'll go out and it'll rain the moment you step out of the door.
