The North American Monsoon is About to Start: Part of the Northwest Will Get A Piece of It!

Late June or early July is the traditional start time for the North American (or Southwest) Monsoon, during which moisture streams northward from Mexico into the southwestern U.S., bringing substantial showers to Arizona, New Mexico, Nevada, and sometimes Oregon, Idaho, and eastern Washington. See the schematic below. Such monsoons are often associated with an area of high pressure over Colorado…