The word "monsoon", originally comes from the Arabic word, "mausim", meaning "a season". It was first used to describe the winds over the Arabian sea, which blow from the northeast for six months and from the southwest for another six months.
In Arizona, the monsoon, begins with the extreme dry heat of May and June, when temperatures rise to 100 degrees and above. As the atmosphere warms, the dry jet stream moves northward and the winds shift up from the south. This shift brings in humidity and moisture from the Sea of Cortez, and the Gulf of Mexico. Once the moist air arrives, the intense summer sun heats the air, creating columbous clouds, which lead to frequent afternoon and evening thunderstorms with a spectacular display of lightning.
Officially, the monsoon starts on June 15th and ends on September 30th.
Flooding causes more deaths in the United States than any other weather-related hazard except severe heat.
In Arizona and New Mexico, floods killed 57 people between 1995 and 2006, while hundreds of others have needed swift water rescues. The economic price tag is also high, costing Arizona, New Mexico, Colorado, and Utah approximately $5 billion between 1972 and 2006.
The Dangers of Flash Flooding
Flash floods can occur within minutes after the onset of a rain storm. They can be deadly because water levels rise quickly and flow like rapids within minutes.
City streets become rivers, because with no drainage system, except for low-lying washes and arroyos the water has nowhere to go and cannot be absorbed into the ground.
Mountainous areas also experience flash floods, as the higher grounds funnel water into the canyons. One tragedy in 1981, killed eight people in the Sabino Canyon area in Tucson, Arizona.
Learn more here.
Posts
