That year, a dry winter influenced by La Niña conditions gave way to a spring and summer that provided no relief. The presence of La Niña invites some comparisons to 2010-2011, when Texas entered its worst drought in recent history. “La Niña makes the jet stream stay farther north than usual, so we don’t get as many cold fronts as we normally would,” Nielsen-Gammon said. In Texas, La Niña tends to cause warmer and drier conditions than normal because of its influence on the jet stream. During La Niña, sea surface temperatures in the southern Pacific Ocean hover at a temperature lower than average. “I don’t think we’re going to have a significant respite from these dry conditions until at least February through March,” Bertetti said.Ī main factor in this winter’s dryness is La Niña, the cold phase of the El Niño Southern Oscillation, a cycle of ocean temperatures that influences weather around the globe. The warm, clear weather could last through the end of March, according to the National Oceanic and Atmospheric Administration. Forecasters are predicting showers as a weak cold front moves into the region this week.īut in the longer term, national forecasters anticipate mild and dry conditions across much of the southern U.S., including Texas. The aquifer could get a boost from scattered thunderstorms expected this Tuesday and Wednesday. Outdoor watering restrictions that limit sprinkler use don’t kick in unless the aquifer’s 10-day average drops to 660 feet or below. 8 board meeting.Īs of Saturday, the Edwards Aquifer below San Antonio stands at 663 feet above mean sea level. Its main source, the Edwards Aquifer, is “a little below historical average for this time of year, mostly because we’re well below rainfall for the fall and winter months,” Paul Bertetti, director of aquifer science for the Edwards Aquifer Authority, which manages pumping of the water source, said in a briefing at the EAA’s Dec. San Antonio gets most of its drinking water from underground aquifers. Canyon Lake is 89 percent full, compared with 93 percent this time last year.
Near San Antonio, Medina Lake is 42 percent full, compared with 79 percent a year ago. Rivers and reservoirs in central and western Texas are running lower than they have over the past few years. “We’re a bit drier than we would have been if temperatures were near normal rather than a few degrees above.” “In that sense, climate change is having its normal effect on dry conditions,” Nielsen-Gammon said. Over the past six months, temperatures across Texas have averaged 1 to 2 degrees higher than normal, which is “about what you’d expect, given climate change,” he said. While droughts are typical in Texas, climate change influences their severity, said Texas State Climatologist John Nielsen-Gammon, a professor of atmospheric sciences at Texas A&M University.
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