Forecasters: Strong chance La Niña returns

Oct. 18—Rain lovers who think it's been too much of a good thing lately should still try to enjoy every drop because a dry stretch lies ahead.

This year's monsoon — which made the top 10 for the wettest since tracking began in 1893 — helped extinguish the largest wildfire in New Mexico history, kept the Rio Grande flowing strong through most of the summer and offered relief from the state's 23-year drought.

Much of the state is now deemed abnormally dry or in moderate drought, the least intense ratings by the U.S. Drought Monitor. That's in sharp contrast to five months ago, when most of the state was immersed in exceptional drought.

But nature is preparing to pull a quick change.

A La Niña weather pattern is brewing for the third year in a row — a relatively rare trend that experts call a "triple dip" — which will push precipitation northward and cause drier-than-normal conditions in the winter and spring.

The Climate Prediction Center estimates there's a 75 percent chance of a La Niña forming by December and going through at least February. After the rainy summer and early fall, many New Mexicans will feel as though they've been pulled right back into the prolonged drought.

It's possible the first months of 2023 will be as dry as they were the year before, said Todd Shoemake, meteorologist for the National Weather Service in Albuquerque.

"It's very unfortunate, but that's kind of what we're looking at," Shoemake said.

Only three or four triple-dip La Niñas have occurred since 1950, and it's unknown how climate change will affect Pacific Ocean weather patterns, he said. What is known is that the changing climate will make weather more unpredictable, he said.

"Overall, [climate change] does seem to have thrown a wrench into long-term forecasting," Shoemake said. "Now, as the climate is evolving and changing so rapidly, it seems our indicators aren't working quite as well as they used to."

So far, the Santa Fe area has received 11.4 inches of rain, well surpassing the year-to-date average of 9 inches, he said. And already it outpaces 2021 and 2020, which got 8.9 inches and 6.3 inches for the entire year, respectively, he said.

Albuquerque showed a more modest year-to-date increase in rain with 8.34 inches, compared to 7.4 inches at the same time last year, Shoemake said. In contrast, Las Vegas, N.M., has seen 11.4 inches so far, on par with Santa Fe but significantly below its average of 14.2 inches.

The region's banner rainy season is a double-edged sword.

Water managers say it has helped a drought-parched region meet supply demands, while fire officials caution it has spurred heavier vegetation that will dry out during the La Niña and make the forests more flammable.

Julie Anne Overton, spokeswoman for the Santa Fe National Forest, said fire managers are experienced in dealing with vegetation and debris turning into flammable fuels during a La Niña, although this time around they'll be thicker than usual.

"They will certainly be aware of all of that vegetation that's due to this year's record monsoon," Overton said. "It will be all about preparation and having the resources when we need them."

The pause on prescribed burns remains in place while the U.S. Forest Service reviews the policies and practices in the aftermath of the devastating Hermits Peak/Calf Canyon Fire. Two prescribed burns that went out of control merged into the monstrous blaze.

Overton said planned burns are the best tool for removing excess vegetation, debris and trees that make a forest more fire prone. They'll resume after agency Chief Randy Moore believes his recommendations for preventing future planned burns from going awry are implemented.

Meanwhile, the head of a regional irrigation district said the ample monsoon and late-season rains carried farmers through the summer growing season and are now helping them with their fall plantings of winter crops.

Rain watering the farmers' crops means more Rio Grande water can be sent downstream so New Mexico can meet its seasonal obligation to Texas and chip away at the debt it owes the Lone Star state, said Jason Casuga, CEO of the Middle Rio Grande Valley Conservancy District.

New Mexico owes Texas about 125,000 acre-feet of water, and state officials won't know until December how much they were able to dent that debt, Casuga said.

An acre-foot is about 326,000 gallons, enough to supply two or three average households for a year.

Casuga said he's not happy about another impending La Niña, which could bring similar water supply challenges as last year.

But this time, the soil will be more moist from all the rain, so it won't soak up runoff from the snowpack melt as it did last year, allowing more to flow into the rivers, Casuga said.

"So there's a glimmer of hope," he said.

This year, the Santa Fe River's inflows into the municipal system were the strongest in the 23 years they've been measured, said Jesse Roach, the city's Water Division director, who called them "extraordinary."

The city had ample water to supply all of its users, including Santa Fe residents and three acequias, while keeping its two reservoirs a quarter filled, which is the maximum amount the city chooses to store, Roach said.

The rain enabled people to irrigate their lawns and gardens without needing the city to supply the water, Roach said.

Rainfall will wane in the coming week, which could mark the prelude to the drier La Niña period.

"It's winding down pretty quickly," Shoemake said.