El Niño Still Strengthening, Expect Wetter Winter, Spring
11/12/16 – Today, NOAA’s Climate Prediction Center issued an update on the current El Niño. It continues to strengthen, with a strong-to-very strong El Niño likely through January-March 2027. Historically, that predicts a wetter than normal winter, with stronger, more frequent storms.
A transition to weaker El Niño or La Niña conditions next spring could also mean less wind sheer and more hurricane activity in 2027.
Increases in Temperature Anomalies from October to November
NOAA’s new ENSO discussion, published today, reports increased temperatures averaging approximately a half degree centigrade in the last month. The next report comes out on December 10.
60% Probability of Exceptional Intensity
NOAA now assigns a 60% probability that El Niño will reach historically exceptional intensity during October–December or November–January. However, its forecast still calls for El Niño to begin weakening in early 2027.
What that Means for Texas
A stronger El Niño during winter generally means a wetter, cooler, and stormier winter across Texas and much of the southern United States. It can also mean warmer, drier conditions across portions of the northern United States.
For the Houston area, the biggest concern is not hurricanes. It is the potential for more frequent rainstorms, prolonged wet periods, and increased winter and spring flooding risk.
The most important meteorological mechanism is the displacement of the subtropical jet stream, which steers storm systems across the southern United States.
During strong El Niño winters, that jet stream tends to become stronger and more active, bringing Pacific storm systems across California, Arizona, and New Mexico into Texas and the Gulf Coast.
The strengthening reinforces the winter weather concern, but does not translate directly into a specific percentage increase in Texas rainfall.
Implications for Houston and San Jacinto River Basin
The U.S. Geological Survey’s South Central Climate Adaptation Science Center has published an especially relevant assessment of the 2026–2027 El Niño. It identifies increased precipitation, stronger winter storm systems, and elevated flood hazards as potential consequences across Texas and neighboring states.
Here is how those changes could affect the San Jacinto Basin.
| Meteorological effect | Potential consequence for Houston |
|---|---|
| More frequent frontal systems | More rain events throughout winter |
| Stronger subtropical jet | More organized storm systems |
| Increased Gulf moisture transport | Potential for heavier rainfall |
| Repeated storms | Less time for saturated soils to drain |
| Greater runoff | Higher flows in Spring Creek, Cypress Creek, and the San Jacinto River |
| Prolonged wet periods | Greater potential for elevated Lake Conroe and Lake Houston levels |
The distinction between total seasonal rainfall and individual storm intensity is important. A winter can be substantially wetter than normal without producing a catastrophic flood. Conversely, one exceptionally intense rainstorm can cause severe flooding even during an otherwise dry winter.
In the San Jacinto Basin, repeated winter rainfall could create a sequence in which one storm raises river levels, the next arrives before those levels recede, and subsequent rainfall produces greater runoff because the watershed is already wet.
This is one reason a strong El Niño can matter to flood management even without tropical cyclones.
El Niño can alter the frequency and location of winter and spring storm systems. It can also increase opportunities for strong wind shear and Gulf moisture to interact.
However, a wetter and cooler winter does not necessarily mean more tornadoes, severe storms or freezing weather. In fact, the USGS assessment notes that extreme Arctic outbreaks such as the February 2021 Texas freeze may be less likely under the typical strong El Niño circulation pattern, although they remain possible.
Bottom Line for Houston: The National Weather Service’s Houston/Galveston office conducted a broader local study of winter precipitation at Bush Intercontinental Airport. They found that 76.5% of El Niño winters had above normal rainfall. But only 33.3% of La Niña winters had above normal rainfall.
Are Winter Impacts Proportional to El Niño Strength?
The relationship between El Niño intensity and weather impacts is not linear. In other words, doubling El Niño strength does not produce twice as much rain, twice as many storms, or twice as much flooding.
Other influences include the Arctic Oscillation, North Atlantic Oscillation, Madden–Julian Oscillation, Gulf sea surface temperatures, and shorter-term weather variability.
NOAA specifically cautions that even very strong El Niño events do not guarantee the expected regional effects.
Keep that umbrella handy!
Posted by Bob Rehak on 11/12/26
3362 Days since Hurricane Harvey
