During the month of July you might start hearing talk about the “monsoon.” But, do you really know what it is?
The North American Monsoon provides summer thunderstorms from California to Colorado and from Mexico to Montana. The area of coverage is basically the southwestern U.S. and Northwest Mexico.
It is sometimes referred to as the Southwest monsoon or the Mexican Monsoon.
The word monsoon simply means a wind that reverses direction. A lot of people when they hear the word “monsoon” tend to think about the torrential flooding rains that typically occur in India and Southeast Asia. Our summer monsoon is not quite that dramatic, but it does provide lots of moisture during what is often the hottest part of our summer. It can also sometimes produce flooding rains with slow moving thunderstorms.
Here is how the Monsoon sets up on the weather map:
High Pressure moves in and centers over the four corners area. This High may hover around Colorado down into the Southwestern U.S. This can produce dry and hot conditions in June and the early part of July. As the summer moves on this area of High Pressure typically starts to move to the east. This helps to shift the overall wind flow pattern to a more southerly direction. The shift in wind flow opens the door for moisture to flow northward from the Pacific Ocean and the Gulf of Mexico.
As a result, Colorado sees a rise in daily afternoon and evening showers and thunderstorms. And this year we need as much water as we can get from the Summer Monsoon.