What type of weather should we expect this winter and how will it affect our water supply?

Winter weather came roaring into Texas in mid-January, bringing with it snow and freezing temperatures to parts of the Brazos River Basin.

Unlike recent winters that were affected by drought, we're entering the winter months with the Brazos River Authority (BRA) water supply reservoirs sitting at 94% full.

According to Aaron Abel, BRA water services manager, "The water supply in the central and lower reservoirs are not as full as those in the upper basin because October was among the driest Octobers on record for the central and lower basin."

The upper basin reservoirs received rain in the fall, which isn’t abnormal since September and October typically usher additional rain events with the start of invading cool fronts and associated storm systems. Typically, the central and lower basin receives more rainfall than the upper region.

Currently, 44% of the central and lower basins are experiencing some form of drought conditions. The upper basin is currently experiencing no drought conditions.

Weather experts are keeping a close eye on the developing La Niña weather pattern, which could enhance drought conditions.

The National Oceanic and Atmospheric Administration (NOAA) forecasters, in collaboration with the National Integrated Drought Information System (NIDIS) warn us to expect drought conditions to persist and worsen across the central and southern Plains of the U.S.

John Nielsen-Gammon, Texas State Climatologist and director of the Southern Regional Climate Center at Texas A&M University explains, "Around mid-December, sea surface temperatures in the equatorial Pacific finally dropped to more than a half degree Celsius below normal."

"The Climate Prediction Center relies on three-month temperature averages to be sure to get a clear signal, so probably the November-January three-month period will be the first with La Niña conditions," Nielsen-Gammon said. "But the sea surface temperatures are expected to recover by late spring, so it probably won't hit the five consecutive month threshold to be considered a La Niña' event'."

La Niña is the cooler counterpart to El Niño in the El Niño/Southern Oscillation (ENSO) system. It occurs when sea surface temperatures in the central and eastern portions of the equatorial Pacific Ocean drop below average. These cooler waters disrupt atmospheric circulation and influence weather patterns worldwide, including across North America.

Historically, La Niña winters bring drier conditions to the southern U.S. and wetter conditions to the Pacific Northwest and parts of the Midwest.

Recent La Niña winters brought some of the most severe winter weather events in state history.

Texas, as a whole, endured the coldest few days in the last 100 years in February, 2021 during winter storm Uri; coined Snowmageddon. Then two years later, Texas had the ice storm in February, 2023.

"The weather in the Brazos River Basin has been affected by La Niña already. Typically, we see a warmer than normal winter with relatively dry conditions and occasional cold-air outbreaks," Nielson-Gammon explains.

La Niña's strength is based on just how much colder than normal the water temperature is in the eastern Pacific Ocean. The colder the water there, the stronger the La Niña.

But according to NASA, as oceans warm globally due to climate change, it's harder for the waters to cool to the levels that define a La Niña, especially a strong one.

"Temperatures have held true to form so far, generally warm except for the cold weather that hit the second week in January," Nielsen-Gammon continues. "Rainfall has been above normal along and upstream of I-20, but below normal farther downstream."

"Because this is going to be a relatively brief and mild La Niña, if it counts as a La Niña at all, it shouldn't have much impact on water supplies," he said. "The above-normal rainfall in the upper Brazos basin guarantees decent moisture in the system even if conditions turn dry now," Nielson-Gammon explained.

Abel agrees, "The BRA system of reservoirs is in good shape for water supply."

Neilson-Gammon reminds us that conditions can change. "Late spring and summer are unpredictable, as we've seen the past few years, and short-term drought is always capable of emerging quickly during the warmer parts of the year."

Areas that usually see steady rainfall during winter might see less precipitation than normal. Temperatures will also be warmer than usual.

NOAA predicts a likelihood for drier-than-average conditions in states bordering the Gulf of America, as well as in Texas and New Mexico. Drought is likely to develop or worsen across portions of the Southwest and Gulf Coast.

While most reservoirs in the BRA's water supply system are full to nearly full, it doesn't mean that water conservation should be ignored, especially when drought conditions increase.

Smart water conservation practices implemented regularly have a direct impact on water usage.

Water conservation practices that are simple and easy to implement this winter include:

• Winterizing outdoor spigots when temperatures drop below freezing.
• Curtailing lawn watering. Dormant lawns don't need to be watered.
• Turning off the water while brushing your teeth or shaving and taking shorter showers.
• Fixing any drips or leaks in sinks or toilets

In addition to water conservation, make sure your home and family are prepared for any variation of winter weather. Visit the Texas Department of Emergency Management (TDEM) for resources on winter weather preparedness actions, road conditions, winter weather terms and more.