When Does Monsoon Start and End in Arizona?
The Arizona Monsoon starts mid July and is a welcome break from the full summer heat. The effects of the Monsoon can look statistically severe, but the intensive rains only last until mid August. While the Monsoon is the most volume of rainfall it is not the only desert rains to fall. Through out the year, brief, sometimes barely noticeable precipitation will fall and evaporate with very little evidence left behind. While the Monsoon storms can halt construction and slow traffic it is really only dangerous if people enter the hazardous areas that are marked for “flash flooding” or “sliding rocks,” and for the Golfer that refuses to heed the dark clouds.
During the Monsoon, the sudden mixture of cool wet air from the South and the hot rising air of the desert can create instant and intense storms, often while the sun is still shining. These localized storms can pound an area with heavy rain, that lead to flash flooding and hail stones that will crack windshields, and cause vehicles to skid on the roadways. Never enter a roadway that is flooded, even a few inches of water rushing can disable a vehicle. While the weather can create these inconveniences, it is the drivers on the roadways and their reactions to the weather that increase the dangers during these storms.
These storms and the mixture of air before the storm clouds form can pick up large amounts of dust that create instances of lightening. During the Arizona Monsoon air friction created by high winds and hot air, pushing through rising hot air will cause friction and the air becomes charged. Once this charge encounters the path of least resistance to the ground, via a treetop, the top of a building or even the upswing of a golf club, the circuit is complete and the current will travel through to the ground. The instances of lightening can occur with little or no warning, and do not always have accompanying thunderclouds.
By the end of August, the bulk of the Arizona Monsoon has calmed, but a few storms will travel in from the South, but these storms are more tourists, bringing the rumble of dust and mostly just a threat of rain. The few light storms that have rainfall will typically chase the sunset, filling the evening sky with golden clouds and a cozy canopy that creates an ambient evening glow that is like no other.