El Niño Implications for Gulf Coast
After three years of La Niña, signs point to the start of El Niño with cooler-than-normal temperatures off the Pacific Coast of North America. Jeff Lindner, Harris County’s meteorologist, says an El Niño could fully develop in the next few months. Here are El Niño implications for the Gulf Coast.
Cooler, Wetter, Fewer Hurricanes
In the south-central United States, major impacts during an El Niño event consist of:
- above-normal precipitation, particularly during winter
- below-normal temperatures, also during winter
- a less active hurricane season, with fewer named storms
In general, stronger winds from the west during El Niño tend to inhibit development of storms trying to approach from the east. Meteorologists call that process “wind shear.” See red arrow in second map below.
CSU Predicts Below-Normal Hurricane Season This Year
Colorado State University hurricane researchers predict a slightly below-average Atlantic hurricane season in 2023, citing the likely development of El Niño as a primary factor.
While most organizations have expressed growing confidence in the development of an El Niño, a few have noted above-average ocean temperatures in the eastern Atlantic that introduce uncertainty and which could actually yield greater activity, particularly if a weaker El Niño event materializes. See below.
South America has had cooler-than-normal waters off its west coast for the last three years, but now those same waters have warmed for the last 3-5 months. And the cooler waters have shifted north of the western coast of the U.S. and Canada.
Jeff Lindner, Harris County’s meteorologist says, “We need to see these conditions hold for a few months for the official declaration of El Niño. Lindner says conditions could likely intensify into a strong El Niño by late this summer or early fall.
El Niño Typically Brings Wetter Weather to Gulf Coast
He also notes that sea surface temperature anomalies of this magnitude can shift weather patterns across the globe.
Locally, Lindner says, “El Nino tends to support wetter and cooler conditions during our fall, winter, and spring months. There is less influence during summer.”
“The threat for heavy rainfall and flooding is generally higher during El Niño periods.”
Jeff Lindner, Harris County Meteorologist
According to Lindner, La Niña tends to correlate with the opposite influences – warmer, drier conditions for Texas or even drought…as many areas have experienced during the most recent La Niña event that started in early 2020.
Not all El Niño events are the same. Other global weather patterns can enhance or interfere with the effects of El Niño.
Lindner believes that the speed with which El Niño conditions form this summer will likely determine the fate of the Atlantic basin hurricane season. “A quicker onset would tend to significantly reduce Atlantic basin activity while an onset more toward early fall may allow a slightly busier and “front loaded” season,” he says.
El Niño patterns tend to favor reduced Caribbean hurricane activity and a higher chance of more sub-tropical development over the mid-Atlantic.
During El Niño years, says Lindner, tropical storms and hurricanes tend to form “in close” in the northern Gulf and off the southeast U.S. coast as tropical waves move into more favorable conditions.
Less Drought Likely
As El Nino develops this summer into the fall, it is likely that Texas and the southern plains will transition toward a wetter pattern. That should lessen or eliminate the ongoing drought across portions of Texas. Lindner expects to see significant improvements by late fall into the winter.
Posted by Bob Rehak on 5/4/2023 based on a press release by Harris County Meteorologist Jeff Lindner
2074 Days since Hurricane Harvey
