Rosa puts 12 million under risk of flood

Now-tropical storm threatens states in Southwest

The remnants of Hurricane Rosa are forecast to bring heavy rain and the threat of flash flooding to the Southwest over the next few days. The now-tropical storm – which had been as strong as a Category 4 hurricane – is poised to make landfall along Mexico’s Baja California Peninsula on Monday evening, where heavy rain was already being reported. Flood watches are in effect across portions of California, Arizona, Nevada and Utah, including the cities of Phoenix, Las Vegas, Flagstaff and Salt Lake City. More than 12 million people are at risk of flooding, the National Weather Service said. Arizona should see the heaviest rain, the National Hurricane Center said, where up to a half-foot of rain is possible in some areas. This could bring “lifethreatening flash flooding” and “dangerous debris flows and landslides,” the hurricane center said. Flash floods are caused by heavy rain. They can turn otherwise calm dry washes, burn scars and urban areas with poor drainage deadly. Last year, a peaceful swimming hole turned into a raging waterway in Payson, Arizona, killing 10 family members. In some desert areas, the rain that’s expected to fall from Rosa is as much rain as would typically fall in an entire year, AccuWeather said. Yuma, Arizona, the USA’s driest city with only about 3.6 inches of rain a year, may see nearly that much the next couple days. Although flooding is a serious concern, some of the rainfall will probably be beneficial since the Southwest is experiencing drought conditions, weather.com said. According to the U.S. Drought Monitor, more than 40 percent of Arizona is experiencing at least extreme drought, the secondhighest category. As of 2 p.m. EDT, the center of Tropical Storm Rosa was 75 miles west of Punta Eugenia, Mexico, and moving to the north-northeast at 12 mph. Rosa had winds of 45 mph. Several school systems in Mexico’s Baja Peninsula were closed Monday as the storm approached the region.

MARK HENLE/THE ARIZONA REPUBLIC Flood watches were in effect in Phoenix. Arizona could get Rosa’s heaviest rain.