outlook+water: La Niña fades away, drought contracts (but extreme drought expands), and the next three months favor hot with dry conditions for the High Plains

SUMMARY:

• Drought conditions (D1–D4) decreased to 53% of the state from 68% of the state four weeks ago; statewide reservoir storage increased to 77% full up from 76% four weeks ago and about 8 percentage points below normal for this time of year.
• La Niña has transitioned to neutral conditions, which are favored through October (with a hint of La Niña this winter).
• Drought is expected to improve over the next three months except in Far West Texas.
• Is an Atlantic Niña fixin’ to form?

I wrote this article on May 4, 2025 (May the 4^th be with you!).

As we transition from La Niña to La Nada conditions in the Pacific, eyes are now on temperatures in the Atlantic. Warmer temperatures correlate to more energy in the sea surface which means potential for that energy to feed tropical systems. However, although temperatures in the mid-Atlantic are higher than normal, they are 2 degrees Fahrenheit cooler than last year and cooler than temperatures away from the equator (USA Today; Figure 1 below).

As I dug deeper into this phenomenon (and what it means for tropical system formation), I came across a National Oceanic and Atmospheric Administration post about Atlantic Niños and Niñas.

Say what?

It seems these are differentiated from their Pacific brothers and sisters by dropping the El’s and La’s. Atlantic Niños and Niñas are caused by upwellings of cold (or warm!) water in the equatorial Atlantic, and they do appear to affect tropical systems. They are also difficult to find information on!

April showers showered more in the North and Northeast Texas than the rest of the state (Figure 2a). However, a sizable part of West and Far West Texas received less than 0.01 inches of rainfall (Figure 2a). Much of the Rio Grande received less than a quarter of an inch, but much of the rest of the state benefitted from at least half to a full inch of rain (Figure 2a). The percent-of-normal map flipped from last month with most of the state getting much more than normal for the month except for the Lower Rio Grande Valley which got much less than normal (Figure 2b).

The amount of the state under drought conditions (D1–D4) decreased from 68% four weeks ago to 53% today (Figure 3a) with improvements over much of the state (Figure 3b). Extreme Drought or worse decreased from 29% of the state four weeks ago to 26% today with exceptional drought increasing from 14% four weeks ago to 15% today (Figure 3a). In all, 64% of the state is abnormally dry or worse (D0–D4; Figure 3a), down from 85% four weeks ago.

The North American Drought Monitor, which runs a month behind current conditions, shows drought across the North American continent but especially in the Southwest (Figure 4a). The drought in the Southwest has gotten more intense and more extensive. The Rio Conchos basin in Mexico, which confluences with the Rio Grande just above Presidio and hosts the largest tributary to the Lower Rio Grande, remains in moderate to extreme drought (Figure 4a).

Conservation storage in Elephant Butte Reservoir—an important source of water for the El Paso area—decreased from 14.2% full four weeks ago to 14.1% more recently (Figure 4b), about 10 percentage points below a rather pitiful median storage of 25% full.

Combined conservation storage in the Amistad and Falcon reservoirs decreased slightly to 20.4% full from 21.5% four weeks ago and is almost 40 percentage points below normal for this time of year and the lowest in at least the past 33 years for this time of year (Figure 4c).

Basins across the state continue to host flows over the past week below historical 25^th, 10^th, and 5^th percentiles (Figure 5a). Statewide reservoir storage is at 77.2% full, up from 75.7% four weeks ago but about 8 percentage points below normal for this time of year (Figure 5b). The orange reservoir in the Dallas-Fort Worth area (the persimmon in a sea of blueberries) is New Terrell City Lake and has dropped from full in early March 2024 (Figure 5c). The Lake is no longer used for water supply and appears to be undergoing long-term maintenance work.

My (drumroll please) Hydrograph of the Month is Lake Arrowhead over yonder near Wichita Falls where big rains have pulled reservoir levels up from below normal to above normal in a matter of days (Figure 5d).

We are under the final La Niña Advisory with a return of neutral conditions in March (Figure 6a). Neutral conditions are favored through August-October with a growing chance of La Nina conditions returning in the late-fall/winter (Figure 6a, b).

Perhaps due to the recent development of La Nada conditions, the U.S. Seasonal Drought Outlook through July now shows drought removal and improvement except in Far West Texas (Figure 7a). The three-month temperature outlook projects (surprise, surprise) above-average temperatures for most of the state (Figure 7b) while the three-month precipitation outlook favors rainfall deficits for the High Plains (Figure 7c).