New Mexico dam nears failure as 25+ states face dangerous flood threat fueled by Pacific tropical systems
A dangerous week-long flash flood threat is spreading from the Southwest into the Plains and Midwest, putting more than 150 million people at risk as moisture from nearby tropical activity fuels intense thunderstorms.
THE TAKEAWAY
A dangerous week-long flash flood threat is spreading from the Southwest into the Plains and Midwest, putting more than 150 million people at risk as moisture from nearby tropical activity fuels intense thunderstorms.
Storms stretching from Texas to Minnesota are being fueled by Hurricane Polo and Tropical Storm Rachel.
A Flash Flood Emergency tagged with a catastrophic threat was issued in New Mexico amid an imminent dam failure Tuesday evening.
A Flood Watch currently covers 10 states, with more states expected to be added in the coming days.
A large dip in the jet stream will pull moisture from these tropical systems north throughout the week, bringing thunderstorms capable of producing lots of rain in a very short amount of time.
Flash flooding was seen Monday across parts of southern Nevada, as moisture from the remnants of another tropical system, Odalys, saturated the ground ahead of more heavy rain this week. Roads in Laughlin experienced debris flows. Roads were also flooded in Crownpoint, New Mexico.
This comes amid an active monsoon season across the Southwest, which has seen deadly flooding across parts of New Mexico and Grand Canyon National Park.
On Tuesday, a Flash Flood Emergency was issued for Doña Ana County after dam operators reported the imminent failure of McLeod Dam in south-central New Mexico.
The Particularly Dangerous Situation-tagged emergency, carrying the highest threat designation of catastrophic, urged residents in rural areas between Garfield and Salem to immediately seek higher ground.
Officials warned that flooding could also impact Highways 187 and 390.
The dam is located roughly 40 miles north-west of Las Cruces, and is in a very rural area in the immediate area, but the FOX Forecast Center warned, if the dam fails, downstream impacts will be likely.
WATCH: RESCUES UNFOLD IN NEW MEXICO AS HURRICANE POLO MOISTURE FUELS STATEWIDE FLOOD THREAT
According to the U.S. Army Corps of Engineers National Inventory of Dams last updated in July 2023, the dam was built in 1953 and stands 25 feet high, stretching 6,774 feet long.
During its most recent inspection in 2023, the dam was listed in "poor" condition with a "high" hazard potential. The Corps defines high-hazard-potential dams as those where failure or misoperation would probably cause loss of human life.
The "poor" condition designation means a dam safety deficiency has been identified, and remedial action is necessary, or uncertainties remain about critical analysis parameters tied to a potential deficiency.
Heavy rain will build through the day on Tuesday across much of the Four Corners, the Texas and Oklahoma Panhandles and parts of the Central Plains.
The remnants of Hurricane Polo, which made landfall in Baja California early Tuesday morning, will rush into New Mexico, bringing wind gusts between 50 and 60 mph in addition to intense rain. Widespread power outages are possible.
A Level 3 out of 4 flash flood risk covers over 230,00 square miles across parts of southern and eastern Arizona, much of New Mexico, southern Colorado, the Texas and Oklahoma Panhandles and southwestern Nebraska.
If this was a state, it would be the third largest in the country behind Alaska and Texas.
The flood threat is expected to peak on Wednesday and Thursday as moisture from Tropical Storm Rachel adds more fuel to the ongoing storm pattern.
In the most recent update from the National Hurricane Center (NHC), Tropical Storm Warnings were issued for the southwestern Mexico coast.
The Level 3 flood threat will shift over Oklahoma and Central Texas, where storms could potentially produce up to 3 inches of rain per hour.
A separate Level 3 threat zone covers southern Colorado and extreme northern New Mexico.
Dallas, which has not seen measurable rain since July 16, is in the path of a significant flood threat, with the dry ground unable to absorb much water.
Oklahoma and Texas will remain at the center of the flash flood threat, which will gradually begin to shift eastward through the end of the week.
Check back for updates on this developing story.
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