Don’t look now, but Texas has entered another drought, with at least 50 percent of the state rated as either abnormally dry or in moderate to severe drought status. But that could change again in the next few months, and you can thank the developing El Niño in the Pacific for promising precipitation prospects, says a Texas A&M University professor.
John Nielsen-Gammon, professor of atmospheric sciences who also serves as the State Climatologist, notes that the El Niño (warmer water conditions than usual in the Central Pacific that tend to affect much of the U.S. weather patterns) could be one of the strongest ever recorded. The strongest ever occurred in 1982-83 and 1997-98, and the current one is expected to rival those two.
“The El Niño now in the Pacific is being called ‘Godzilla’ because it is turning out to be so strong,” Nielsen-Gammon says.
“But for Texas, I would term it more of a ‘Goliath’ because history shows that these strong El Niños can be disappointing. With a sustained El Niño all but guaranteed, history says that above-average rainfall is likely on a statewide basis. Of the 12 most intense El Niño events since 1900, 11 have produced above-normal precipitation from October through April.”
But there could be a wild card this year, Nielsen-Gammon points out.
“The most intense El Niño events did not produce the greatest amount of precipitation, at least for Texas,” he adds.
“During the two strongest El Niños, rainfall amounts were only about five percent greater than normal. It’s possible that there might be a ‘sweet spot’ for El Niños that produces the biggest effect on wintertime rainfall in Texas, and these strong events tend to overshoot that sweet spot. But with only two such events to look back on, it’s difficult to know whether all super-strong El Niños will be Goliaths – big but not that effective.”
He notes that the greatest amount of rainfall during a strong El Niño event occurred in 1991, when the Christmas Flood event hit the Brazos, Colorado, and Guadalupe Rivers with heavy rainfall.
None of the state is in extreme or exceptional drought status, the two highest designations, though that could change when the U.S. Drought Monitor is updated on Thursday. Northeast Texas and much of Central and South Texas remain on the very dry side, with Rocksprings receiving barely half an inch of rain since May 30; Escobas, with only .03 inches since June 22; Thornton, with .01 inches since June 28, and Burnet with .25 inches since June 29.
Nielsen-Gammon adds, “Drought relief will not come immediately, and it may arrive in different parts of the state at different times. In South Texas, elevated precipitation during El Niño years typically starts in December, while it may arrive as early as October in locations farther north.”
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