AUSTIN (KXAN)– The predicted changeover from the current multi-year La Niña pattern to El Niño next year could have large-scale changes on our local weather.

The warmer, drier-than-normal weather, made more likely by La Niña, has indeed had a hand in our current drought conditions, as well as in Lake Travis levels dipping to their lowest since 2015. We first warned you last week, however, how new projections from the NOAA Climate Prediction Center call for the current “triple-dip” three-year La Niña pattern to end in 2023, and an El Niño pattern to begin.

ENSO probabilities
ENSO probabilities through summer 2023 with red bars indicating the likely return of El Niño conditions (NOAA Climate Prediction Center)

The predicted change to El Niño conditions means that waters in the Eastern Pacific Ocean near the Equator warm up, shifting the storm track toward Texas and supercharging systems with more moisture and rainfall.

El Nino weather pattern and storm track
Typical El Niño weather pattern and storm track

The last two El Niño patterns were in 2015 and 2018/2019. During those years, the Austin area averaged wetter-than-normal conditions and was also subjected to several devastating floods. The current La Niña pattern began in 2020, and Austin’s rainfall since that time has generally been drier than average.

Austin area rainfall comparison between El Nino and La Nina years
Austin area rainfall comparison during 2015, 2018/2019 El Niño versus the current three-year La Niña pattern.

In 2015, 59.96 inches of rain fell in Austin. Central Texas experienced multiple rounds of deadly flash flooding, from the Blanco River and Shoal Creek floods in May to the 500-year rainfall event in southeastern Travis County in October that produced 15 inches of rain in one day.

More recently, October 2018 floods also occurred in an El Niño pattern. Two concurrent flood waves from the Llano River and upstream of Lake Buchanan converged on Lake LBJ, sending homes underwater and washing docks and boats downstream. Boats flowed freely over Max Starcke Dam into Lake Travis. Sediment washed into our lakes from the flood prompted a week-long City of Austin boil water notice and set the stage for future toxic algae growth in Lady Bird Lake.

But since 2020 when the pattern switched to La Niña, the Austin area has generally seen below-normal rainfall. Year-to-date in 2022, Camp Mabry has tallied just 24.74 inches compared to the average of nearly 35 inches.

While next year’s potential El Niño pattern does not guarantee flooding, it does make flooding more likely. Stay with the KXAN First Warning Weather team as the large-scale pattern changes.