What is the North American Monsoon? The North American Monsoon is the general change of weather conditions from hot and dry to wet and stormy for a large portion of the southwest United States from May or June until September. The definition of monsoon, according to NOAA, is “a seasonal reversal of wind patterns changing atmospheric circulation and precipitation, which results in a pattern of wet […] Brains WeatherBrains | August 11, 2021 0 Comments