No one was killed in the ensuing flood but 300 cows drowned. The summer monsoons can have deadly consequences for people caught in the wrong place. The term first applied to winds off the Arabian Sea that blow for six months from the northeast and for six months from the southwest. The Southwest monsoon season normally lasts from July through September, McQueen said. The weather system typically affects Nevada, Arizona, Utah and New Mexico, but the thunderheads can travel as far north as Idaho and Wyoming, he said.
Weather experts predict the monsoon season is going to be even more severe in coming decades.
The American Southwest and the Las Vegas Valley could become much wetter, if climate patterns change as rapidly as predicted by the National Assessment of Climate Study released last week. The study, ordered by Congress in 1990, predicts major changes in weather patterns in the next 50 to 100 years, including more rain and flooding in the Southwest in winter months as well as the summer months from July through September. For the Clark County Regional Flood Control District, keeping up with the growing population has become more than a full-time job even without a climate change to contend with. That basin has been expanded to prepare for this summer's storms. Flooding is still fresh in the minds of some Las Vegas Valley residents who got first-hand looks at the awesome power of a flashflood during last year's storm.