Flash flood watches were issued for five states as Tropical Storm Odile took aim at the Southwest on Tuesday after slamming into Mexico's Baja California peninsula.
Residents in parts of southern California, Nevada, Arizona, New Mexico, and Texas were warned to "be ready to take quick action" by the National Weather Service. Between two and five inches of rain were expected by late Thursday, authorities warned.
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The region is still recovering from Hurricane Norbert last week and officials warned the floods could bring dangerous debris flows. For many residents in and around Phoenix, "the memories are just too fresh to ignore," NBC station KPNX reported.
Other cities under threat were Flagstaff, Yuma, Tucson, Las Vegas and Salt Lake City.
Odile was downgraded from a hurricane to a tropical storm Monday and was expected to be reduced further to a tropical depression Tuesday or Wednesday.
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In Mexico, it damaged megaresort hotels in Cabo San Lucas as well as fishing villages. More than 130 people were injured and tens of thousands of tourists were trapped as airports suffered damage. At 2 a.m. local time (5 a.m. ET), Odile was about 25 miles west-northwest of Santa Rosalia, Mexico.
—By Alexander Smith, NBC News