Flash flooding kills 3 people in New Mexico as Southwest faces more dangerous rain

The Southwest faces a barrage of intense rain this week as rounds of storms are tapping into unusually moisture-rich air being pulled north from Baja California, after flash flooding in New Mexico killed three people early Wednesday.

Officers responded at around 12:30 a.m. local time to a report of three people washed away by flooding near Newcomb, New Mexico, on the Navajo Nation. Police discovered two adults and one juvenile on scene, the Navajo Police Department said in a statement. All three were pronounced dead. The department declined to provide further details about the deaths when contacted by CNN, citing concern for the family’s privacy.

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Rainfall over Newcomb began Tuesday afternoon around 4:30 p.m. and lingered intermittently until just after midnight. The area saw around 0.5 inches to 1 inch of rain in total, with most of it falling within an hour Tuesday evening.

Wednesday’s storms prompted a rare Level 3 of 4 risk of flooding rainfall for parts of Arizona and New Mexico, including Phoenix and Tucson. Phoenix had not faced a flood risk that high since 2022.

More than 3 inches of rain fell in just three hours around the Phoenix metro area midday Wednesday, flooding multiple locations in the Phoenix area.

Officials reported inundated roads and stranded vehicles where drivers had to be rescued in Scottsdale and Mesa, CNN affiliate KPNX reported. First responders were called to a water rescue just south of Phoenix for a car stuck in floodwater with two people inside, CNN affiliate KTVK reported, citing the Maricopa County Sheriff’s Office.

Flood threat shifts east

Rain chances will drop sharply around Phoenix Thursday as drier air moves in. Farther southeast, storms could still produce locally heavy rain, particularly south and east of Tucson.

Western and central New Mexico will remain vulnerable to flash flooding Thursday as more storms develop in the afternoon and evening, especially over the mountains. Repeated downpours over the same areas could send water rushing through normally dry arroyos and low-water crossings.

The heavy rain threat will gradually diminish in New Mexico Friday and Saturday as drier air spreads east.

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Soil across the region is generally dry and compacted, so rainfall quickly runs off the surface rather than soaking in. When combined with steep and narrow terrain, that runoff can quickly turn into fast-moving flash floods, sometimes far from where the heaviest rain actually fell.

New Mexico’s Sacramento Mountains near Ruidoso are particularly at risk for flash flooding and debris flows due to the wildfire-scarred ground that absorbs even less water than the surrounding terrain typically does. The fast-moving mix of mud, rock and burned vegetation can be even more destructive than floodwater alone.

Hikers at the Grand Canyon, Utah’s Zion National Park and other wilderness areas s hould be on alert for sudden flooding, since normally dry ground, including slot canyons, can quickly fill with surging floodwater.

This flooding is unfolding during the Southwest monsoon, when shifting winds pull moisture into the US Southwest, fueling thunderstorms. The monsoon season typically runs from mid-June through September, with the region now in its final stretch.

But this bout of torrential rain is being enhanced by a tropical disturbance that tracked up the Gulf of California and is now in northern Mexico. The system is providing extra moisture and energy for storms to tap into.

Extreme rainfall is becoming more common as planet-warming pollution pushes global temperatures higher because warmer air can hold more moisture.

This story has been updated with additional information.

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