Why El Niño Monsoons Won’t Provide Cure To Lake Mead Water Crisis
Monsoon rainfall is expected to hit parts of the drought-stricken Southwest this week, bringing some risk of flash flooding but offering little help to the depleted Colorado River system.
While the moisture could provide localized, short-term drought relief, meteorologists say it will not deliver the prolonged rain and mountain snow needed to substantially improve conditions at Lake Mead and other major reservoirs.
“Don’t expect much help at all for the Colorado River Basin,” Alex Wallace, on-camera meteorologist at The Weather Channel, told Newsweek. “There may be some areas that pick up a couple of inches of rain over the next few days but to truly get back to normal, they need a lot more.”
In an email sent to Newsweek on Tuesday, AccuWeather said its meteorologists forecast moderate rainfall across the region through Friday, with the heaviest precipitation expected in Western and Northern New Mexico, eastern Arizona and Southwestern Colorado.
The company said a “surge” of tropical moisture is likely to bring repeated rounds of showers and thunderstorms to the Southwest, which could provide drought relief but also raise the risk of flash flooding in areas.
AccuWeather said the pattern is associated with the seasonal monsoon, historically influenced by El Niño, while noting that the strength of the North American Monsoon is also shaped by upper-level high pressure patterns and the transport of atmospheric moisture.
On Wednesday, AccuWeather said rainfall of 1 to 2 inches is forecast through Thursday across the interior Southwest. Much of Central and Eastern Arizona, including Phoenix and Tucson, could see 2 to 4 inches.
AccuWeather cautioned, however, that while the expected rainfall may offer some short-term relief in parts of the drought-affected Colorado River Basin, it is unlikely to make up for years of drought and water shortages.
“This region has been suffering from a multi-decadal drought since the mid-1990s. It’s long-term, and that is why the Colorado Basin’s rivers and reservoirs are near record lows,” AccuWeather lead long-range expert Paul Pastelok said in the Tuesday email. Lake Mead dropped to approximately 1,040 feet in August 2026, surpassing previous low marks from the 2022 drought.
“Over time, we continue to see the rollover impacts each year and river levels just get worse. The region needs prolonged stretches of rain and snow over several years during the winter to really reverse the trend.”
Why the Colorado River Matters
The Colorado River is about 1,400 miles long and its basin covers approximately 250,000 square miles. The river supports water supplies, hydropower, recreation and wildlife habitat across seven U.S. states and Mexico.
According to the Bureau of Reclamation, some 40 million people rely on the river for municipal water, and it sustains 5.5 million acres of farmland. The agency also says the river’s hydroelectric facilities produce more than 8 billion kilowatt-hours annually, enough to meet the needs of approximately 700,000 homes.
Lakes Mead and Powell—the first- and second-largest reservoirs in the U.S., respectively—both plummeted to record lows in August following what federal water managers described as prolonged drought and the lowest snowpack on record.
“The monsoon has certainly provided the Southwest the bulk share of the rain they will see for the year but when you look at the numbers, it has essentially been an average, if not slightly below average, season of rainfall,” said Wallace. “Since the onset of the monsoon, there hasn’t been a substantial change in the drought situation across the Southwest.
“The rain expected for the remainder of this week will be beneficial and there will be some local improvement to the drought. However, overall, I wouldn’t expect to see whole category changes in the amount of drought in the region.”
Wallace added that meaningful long-term drought relief would likely require multiple years of favorable conditions, including wet monsoon seasons and snowy winters. The meteorologist noted that strong snowpack is especially important because melting snow ultimately feeds water into the Colorado River Basin.
“The bottom line is that if we are looking for some long-term drought relief, we should be hoping for winters filled with snow piling up,” said Wallace.
As the current Colorado River operating rules expire at the end of 2026, negotiations and federal decisions over a post-2026 framework will determine how water shortages and reservoir operations are managed amid continuing drought and declining river flows. The seven basin states remain divided over how the shrinking river supply and future cutbacks should be shared between the Upper and Lower Basins, with no consensus framework reached.
Contact Newsweek editors on this story: Matthew Robinson and James Debens
