Last Updated Oct 1, 2018 11:10 AM EDT
MEXICO CITY — Tropical Storm Rosa neared Mexico’s Baja California on Monday, spreading heavy rains that were projected to extend into a drenching of the Southwest U.S. Forecasters said the rain may cause “life-threatening flash flooding.”
The U.S. National Hurricane Center said the center of Rosa, which was a hurricane until late Sunday, should hit Baja California and Sonora state late Monday, bringing 3 to 6 inches of rain. It’s then expected to move quickly northwestward as it weakens, bringing 2 to 4 inches of rain to central and southern Arizona and 1 to 2 inches to the rest of the desert Southwest, Central Rockies and Great Basin.
Some isolated areas might experience more. “These rainfall amounts may produce life-threatening flash flooding,” the hurricane center said in an advisory early Monday. “Dangerous debris flows and landslides are also possible in mountainous terrain.”
The National Weather Service earlier announced flash flood watches through Wednesday for areas including southern Nevada, southeastern California, southwestern and central Utah and the western two-thirds of Arizona. Forecasts call for heavy rainfall in the watch areas, which include Las Vegas, Phoenix and Salt Lake City.
A map made by the National Hurricane Center shows the projected path of Tropical Storm Rosa as of 8 a.m. ET on Oct. 1, 2018.
National Hurricane Center
On Monday morning, Rosa had maximum sustained winds of 45 mph and was centered about 90 miles west-southwest of Punta Eugenia in Mexico. It was heading north-northeast at 12 mph.
Meanwhile, Tropical Storm Sergio was growing in the Pacific and could become a hurricane Monday, though it posed no immediate threat to land. Sergio had winds of 70 mph Monday morning and was centered about 625 miles southwest of Manzanillo, Mexico.
The storm was moving west at 14 mph.
A map made by the National Hurricane Center shows the projected path of Tropical Storm Sergio as of 5 a.m. ET on Oct. 1, 2018.
National Hurricane Center
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