It's 2025 and La Niña still hasn't formed in the Pacific. Here's what that means for winter in Texas.

Colorful maps showing forecasts of snow and frigid temperatures are being splashed across social media feeds, stirring deep feelings of dread in those who remember the deadly deep freeze of February 2021 that led to widespread water and power outages across Texas.

This winter was initially expected to be influenced by the emergence of La Niña, which is the cooling of tropical waters in the eastern Pacific. During La Niña winters, Texas tends to be warmer and drier than normal, but La Niña has yet to fully form. So, what role will the delayed onset of La Niña play in this upcoming blast of cold weather? What could this mean for Texas’s winter?

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What is La Niña?

La Niña is a natural climatic event marked by unusually cooler sea-surface temperatures in the central and eastern Pacific Ocean along the equator. During La Niña events, powerful trade winds flow from east to west, driving warm surface water towards Asia and Australia. Consequently, colder and nutrient-rich waters are drawn upward from the depths along the western coast of South America.

Conversely, the warming of these waters is called El Niño. These two phenomena are part of the broader El Niño-Southern Oscillation, or ENSO, system. These shifts in equatorial ocean temperatures can influence global weather patterns, including in Texas.

TEMP TRACKER: You can see how far above or below normal temperatures are forecast to be where you live.

La Niña conditions have a 59% chance to emerge by the end of the month. If La Niña does officially develop, it’s expected to be brief as a transition to ENSO-neutral is likely to take place between March and May.

Sea-surface temperatures in the central and eastern Pacific indicate the presence of La Niña, but other factors are involved. The observed wind direction in the lower and upper levels of the atmosphere, coupled with placement of clustered thunderstorm activity, also indicate the presence of ENSO-neutral status in the eastern Pacific.

How might a brief La Niña affect Texas winter?

Historically, La Niña leads to winter weather in Texas that is warmer and drier than normal, but this doesn’t prevent freeze outbreaks.

John Nielsen-Gammon, state climatologist for Texas and director of the Southern Regional Climate Center, explained last October that the state’s risk for extreme cold increases during La Niña winters. This is partly because the cold weather La Niña typically brings is from the northern Great Plains and central Canada.

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Since meteorological winter began on Dec. 1, some context clues have emerged that indicate how ENSO-neutral conditions have influenced winter in Texas so far. For example, the eastern half of Texas has gotten quite a bit more rain than normal. The Piney Woods of East Texas had an abundance of rain, with Nacogdoches and Carthage seeing 4 to 6 inches more rain than normal.

La Niña’s fingerprints are more clearly recognized across Central and South Texas, where December rainfall totaled an inch or more below normal.

This winter, whether you’re in Texas, Maine or Montana, is not likely to be a “normal” La Niña winter. The presence of ENSO-neutral conditions mean there are a host of other lesser-known climate variations that can influence, or even seemingly override, weather patterns.

Other states, like Montana and Wyoming, typically have a much colder winter than normal during La Niña. This winter, however, has brought unusually warm weather. Texas, which often sees warmer La Niña winters, is experiencing a temperature pattern closer to normal.