What is a monsoon?

With the North American Monsoon forming over the southwestern United States and Mexico every summer, a question might come up as to what is a monsoon?

The term "monsoon" actually refers to seasonal winds and has origins from the Arabic word "mausim", "a season". So, a monsoon is really an indication of a seasonal wind shift and, importantly, a wind shift that brings moisture into a region to fuel daily bouts of thunderstorms. This atmospheric alignment of favorable winds and moisture transport occurs annually to bring a summer rainy season for parts of North America, including Mexico, Arizona, New Mexico, and western Texas. At times monsoonal moisture can even penetrate deeper into Nevada, Utah, Colorado, and southern California.

Officially, the North American Monsoon season is June 15th to September 30th; however, weather is not bound to a calendar! You will notice during any monsoon season that there are periods of active weather mixed with tranquil days called "bursts" and "breaks", respectively. This is typical as moisture and atmospheric instability needed for thunderstorms can fluctuate even daily as the prevailing monsoon circulation pattern tends to periodically shift throughout the summer months. It really is a challenging time for weather forecasting!

Photo Credit: Jonny William Malloy

Learn more about the monsoon and thunderstorm development!

WHAT IS THE NORTH AMERICAN MONSOON EXTENT?

HOW DO WE PERCEIVE A MONSOON SEASON?

CAN A WET WINTER LEAD TO A DRIER MONSOON?

CAN A WET WINTER LEAD TO A DRIER MONSOON? (PART II)

MONSOON FLASH FLOODING: IT CAN HAPPEN IN A FLASH!

WHY DO MONSOON THUNDERSTORMS FAVOR THE MOUNTAINS?

MONSOON AIR QUALITY: AN INTRODUCTION

DO THUNDERSTORMS HAVE FAMILY TREES?

HOW TO SPOT A SEVERE THUNDERSTORM?

WHAT IS THAT “CAP” LOOKING CLOUD ABOVE A THUNDERSTORM?

WHY ARE THUNDERSTORMS "LUMPY" LOOKING?

IMPORTANCE OF MONSOON RIDGE PLACEMENT

WHY DO CLOUDS FLOAT IN THE AIR?