El Niño could provide wet winter
With Central Texas preparing for another round of heavy rain this weekend, the state’s climate expert says the soaking could continue with an El Niño weather pattern setting the stage for a wet winter and spring.
Climatologist John Nielsen-Gammon of Texas A&M University says long-term forecasts show a weak to moderate El Niño, a seasonal phenomenon that occurs every few years when surface temperatures in the tropical Pacific Ocean heat up and trade winds subside, creating a stronger jet stream and potentially kicking up storms in the southern United States.
The climate pattern likely will mean above-average rainfall in Texas from October to May, Nielsen-Gammon said, though it’s too soon to tell if it will make temperatures warmer or colder this winter.
“El Niño tends to make temperatures cooler than normal,” Nielsen-Gammon said. “But we also have climate change and things are becoming warmer. Those two effects are comparable in magnitude and tend to cancel each other.”
More likely we’ll see near-normal temperatures, he said, despite a Farmers’ Almanac warning of a “stinging cold” winter in Texas.
Cooler, wetter weather would be welcomed by many after one of the hottest and driest summers on record.
The average temperature in Austin this summer was 87.6 degrees, making it the third-warmest ever recorded. The city’s summer rainfall came up 2 inches below average, and the state’s rain total was 2.5 inches below normal, worsening drought conditions in South and Central Texas and the Panhandle region.
September has gotten off to a good start so far, with 4 inches of rain recorded at Austin’s main weather station at Camp Mabry, 6.35 inches in Georgetown, more than 11 inches in San Antonio and nearly 14 inches in Galveston, according to the National Weather Service.
Pastures and hay meadows are turning green, farmers are shutting off their irrigation systems, and springs and rivers are starting to fill, according to the latest Texas A&M crop and weather report. The only ones really suffering are cotton farmers, who need dry weather in September when their cotton bolls form, Nielsen-Gammon said.
“We are mainly past the time for other crops, but it will provide a good start for cool season grasses for ranchers and for getting the winter wheat crop established,” he said. “If it keeps going like this, we should start seeing inflows return to normal.”
That improves water supplies for Austin and other parts of Central Texas, Nielsen-Gammon said. “With the benefits for them, it also means that rice farmers downstream will be able to utilize water for growing crops there.”
The latest map by the U.S. Drought Monitor shows about 32 percent of the state is now drought-free, compared with 20 percent last week. That means 68 percent of the state is still experiencing some level of drought conditions, compared with about 8 percent at this time last year. But forecasters are optimistic that will change soon.
A tropical system brewing in the Gulf of Mexico is expected to make landfall in South Texas on Friday, bringing heavy rain to parts of the Austin area most of the weekend. The National Hurricane Center on Thursday lowered the chances of the system forming into a cyclone from 70 to 50 percent.
“Regardless of whether it stays just the open wave disturbance or whether it does form a closed cyclone, it’s going to bring rain to Central Texas,” weather service meteorologist Aaron Treadway said. “As for when it is going to come and how much, it looks like for the Austin area, rain chances really start to pick up Friday afternoon and will continue through the day on Sunday.”
The weather service expects 2 to 4 inches of rain to fall along the coast, in San Antonio and the Hill Country, and up to 8 inches in isolated areas. The Austin metro area should see about 1 to 2 inches, the service says.
Treadway said flooding is possible, especially in western Travis and Bastrop counties and in the Hill Country, where between 6 and 10 inches of rain already has fallen in the past 10 days.
“Those areas are a little more prone to flooding because of how saturated the ground is,” he said.
Anyone heading to sporting events this weekend in Austin should take heed, meteorologists say. No severe weather is expected but wind gusts could top 30 mph, and a flash flood watch is in effect through Saturday for Comal, Guadalupe and Bexar counties, including the city of New Braunfels, the weather service says. Temperatures could climb into the upper 80s.
Rain will remain in the forecast through the middle of next week, but chances will be slight starting Sunday night, at about 20 percent. Afternoon sea breezes typical for this time of year in Austin could bring isolated showers, Treadway said. The entire region is expected to dry out by the middle of next week, when temperatures return to the lower 90s.