Central Texas is grappling with the aftermath of devastating floods that have claimed nearly 70 lives, including children at a summer camp along the banks of the Guadalupe River. The torrential rains, which dumped nearly 14 inches in just five hours in areas west of Austin, have revealed significant shortcomings in disaster forecasting capabilities amid a changing climate.
Drone footage showed just how far the flooding reached. Whole communities were left underwater, as fast-moving floodwaters gushed through the streets of small towns. Even while the waters recede outside of San Antonio and Austin, hundreds of volunteers in rescue operations are still searching communities. They are looking for at least 12 people still missing since the flood.
Meteorological data indicates that the moisture content in the atmosphere was “above the 99th climatological percentile,” a stark contrast to normal conditions. Whether due to poor management or not, this catastrophic climate change fueled deluge has raised the discussion on the outcomes of climate change. Under a stable climate, we would only expect that much rain every 1,000 years.
As the situation developed, the Austin/San Antonio office continued to announce additional flood watches from late Thursday afternoon. They advised communities to prepare for “catastrophic freshwater flooding” as rainfall totals were predicted to be between 5 and 7 inches. Warnings began emerging along with warnings that the area was particularly vulnerable to flash flooding. That’s particularly the case in “flash flood alley,” a region where deep tropical moisture and humid, slow-moving storms often intersect over hilly terrain.
This year’s extreme flooding has underscored some dangerous trends when it comes to rainfall intensity for Central Texas. Over the last few decades, meteorological trends across the state have indicated a dramatic increase in rainfall intensity. This trend has caused significant concern to scientists and emergency management officials. The impact of Tropical Storm Barry was crucial to this week’s deluge, worsening already fragile conditions.
On Thursday, soundings from weather balloons gave information right over Del Rio. In fact, that revealed record levels of moisture in the upper atmosphere above Central Texas. With today’s weather forecasting technology, we can predict dangerous, near-record rainfall in a given region 24 hours ahead of time. It doesn’t do a good job of providing warnings for acute flooding incidents, especially on the hyper-local scale.
On Friday, Kerrville measured over 10 inches (25 centimeters) of rain in only three hours. Such unprecedented totals only happen once in a normal 500-year period. This points to the increasing absence of traditional or normal weather patterns. The torrential inundation of rain noted with several flooding index points flooded drainage systems and caused fast and deadly flash flooding in many communities.
As people work to rescue and recover from this disaster, hundreds of people have already been rescued from floodwaters. Our experience navigating this crisis has underscored our country’s urgent need for disaster preparedness. As the nature of climate threats changes, we need to get better at deploying these response strategies. Emergency responders are working around the clock to find missing persons and rescue those trapped by the flooding, and their efforts should not be undermined.