Monsoon Season

After living in the severe winter weather of Western New York for a lot of years, we traded the snow in for sun and the high desert of southeast Arizona in 2003. Here sunny days are the norm and clouds nary sprout until it's monsoon season. The official rainy season is from June 15 to September 15. Most natives don't want it to start until July 4 because there's some superstition that the rain will be cut short. Thus the saying - "Rain in June, no monsoon." It's been our experience that it starts whenever it's good and ready with a bit of rain coming in June, but the majority arriving in July and August.

The monsoon is a well documented weather pattern peculiar  not only to India and other exotic regions, but the American Southwest. During the winter, wind flow in Arizona comes from the west or northwest. When things begin to heat up, wind patterns begin to change to the south or southeasterly directions gathering moisture from the Pacific and pulling it up through Mexico and into Arizona. Temperature actually has a lot to do with the monsoon setup. June is our hottest month and the Arizona State University has this to say:

Such a change, together with daytime heating, is the key to the Arizona monsoon. This wind shift is the result of two meteorological changes:

• The movement northward from winter to summer of the huge upper air subtropical high pressure cells, specifically the so-called Bermuda High (H).
• In addition, the intense heating of the desert creates rising air and surface low pressure (called a thermal low) in the Mohave (L).

Now we know some of the boring technical stuff about why it happens, which if you dig a little deeper remains a bit of a mystery even to the people in the know -- meteorologists. What I know about it is this:

• The monsoon brings the most spectacular T-storms you'll ever see. We've enjoyed an electrical show of massive proportions over the mountains many times from the patio.  It's not safe of course to be outside, but it's a bit of a rush and we don't get out much anyway.
• It's the chance to stand and watch it rain. After experiencing so much precipitation in New York, I never thought rain would be fascinating, but it is. In fact, when we first moved here, people who'd been in Arizona awhile told us we would stop everything to watch and it's true.
• My gardens explode overnight and grass appears within days. So much remains dormant until the rains begin, it's a blast of green.  This makes my husband happy because he doesn't have to mow very much or sometimes at all depending on rainfall.
• Weeds appear overnight too and garden maintenance becomes a primary task.
• Rain is unpredictable. The road above us may get a deluge and we get nothing. Or it can flood in the canyons and we watch it all from afar. Or we get a couple of inches that produce a pond in the front yard and friends down the road get only a light shower.
• Humidity hits and our skin is temporarily changed from reptilian to human for a few months. Lotion is isn't quite as necessary, but sunscreen certainly is.

If it's a generous monsoon, we'll get over 12 inches of rain. Rain is scarce the rest of the year with unreliable winter storms and the occasional tropical storm that tracks up through the area.  The monsoon hasn't brought a lot of rain so far this year--maybe an inch or a little more. We'll see how it goes and whether David will have to mow or not.

Photo by Steven Love