After last weekend’s deadly floods in Arizona, more life-threatening flash flooding is possible in Arizona and throughout the desert southwest over the next few days.
Flash Flood Watches have been posted by the National Weather Service (NWS) across most of the Grand Canyon State for the possibility of over an inch of rainfall throughout much of the state on Tuesday and into Wednesday.
But, as is often the case with flash flooding, it’s not necessarily the amount of rain that’s as concerning as much as the rainfall rates. An inch or even a half inch of rainfall in an hour or less can lead to serious flooding in a desert-laden part of the country, where the ground has difficulty absorbing heavy rain.
Last weekend, a torrential downpour near Payson, Arizona led to at least nine deaths.
The hit-or-miss nature of monsoonal moisture can mean places like Tucson, Arizona get pounded with nearly three inches of rain in just the last week, while Phoenix has only seen 0.45″ so far this month (through Monday).
Monsoons are an annual reversal of winds caused by the scorching heat of early summer, leading to moisture being funneled from the Gulf of Mexico into the Southwest, leading to tropical downpours in desert areas. Monsoons are a vital water source for the region, supplying as much as half of the area’s typical annual rainfall, but flash flooding is a common hazard with monsoon rain events.
Stay with WeatherNation for the latest on the monsoon and possible flooding.
For WeatherNation: Meteorologist Chris Bianchi