San Antonio is now entering its hottest and driest period of the year as the Edwards Aquifer continues to drop.
But at least one expert expressed a lot of confidence in the aquifer's ability to continue to deliver water to more than two million people.
Paul Bertetti, a senior researcher at the Edwards Aquifer Authority, which manages the porous underground limestone reservoir that collects rainwater, had no fears it will run dry.
"The aquifer is very good at refilling when it does rain," he said. "It's very resilient. There's a lot of water there, so it's not like we'll run out of water."
Nevertheless, he said Stage 4 water pumping restrictions on major aquifer users could be just weeks away.
Stage 4 begins when the aquifer dips to a 10-day average of 630 feet. Water pumpers have to cut back 44% under Stage 4.
The San Antonio Water System reported it will cut back aquifer usage if Stage 4 is declared, but customers can still follow Stage 2 restrictions because the utility draws from other water sources.
Stage 5 and further pumping restrictions begin at 625 feet, but Bertetti believed that could be avoided this summer.
"We probably have another couple of weeks before we might go into Stage 4. If we extend that and we continue to have maybe normal rainfall, we'll probably stay in Stage 4 for a couple of months — and ideally by October we'll be on the upswing."
Bertetti said heavy rains from a tropical disturbance could be a drought buster. The National Weather Service has predicted an above average season for Atlantic hurricanes.
Rains over the Hill Country and the Edwards Plateau to its north run off into the aquifer through holes and cracks in the ground's surface into what's known as the recharge zone, which runs under upper Uvalde, Medina, and Bexar counties and northward along I-35 toward Austin.
Tuesday through Thursday will be the hottest days of a hot week for San Antonio, with air temperatures near 101 and heat indices around 110. Highs for the rest of the week will push near 100 through at least Saturday.
On Wednesday, those heat indices will rise to 112 in the Hill Country and 117 on the Rio Grande.
Heat advisories are likely Tuesday through Thursday. Forecasters said residents can avoid heat related illnesses by drinking plenty of water, wearing loose-fitting and light-colored clothing, staying in an air-conditioned room, or if working outside, by taking frequent breaks in the shade.