AUSTIN (KXAN) — Torrential rains brought flash flooding to portions of Austin on Sunday after nearly double the month’s worth of rain fell in less than 2 hours.
Camp Mabry, the official city reporting location for Austin, was just on the edge of the heaviest rains, and still tallied up 2.4 inches for the day, which almost exceeds the average monthly rainfall of 2.74″.
According to rain gauges monitored by the Lower Colorado River Authority (LCRA) that were located under the heaviest rains on Sunday, portions of downtown Austin received nearly twice what was recorded at Camp Mabry.
Even during Austin’s wettest months of the year, a 24-hour rainfall total of nearly five inches is very uncommon. But, as our global climate continues to change due to anthropogenic influence, weather extremes like Sunday are actually increasing.
According to ClimateCentral.org, a warmer climate supercharges the water cycle by causing more water to evaporate, allowing the atmosphere to hold more water vapor. Increased water vapor storage in the atmosphere means more water can then be condensed into rain and more rain falls to the surface.
The above graphic, courtesy of ClimateCentral.org, plots the heaviest rainfall total for each year since 1950 for Austin. While there are some smaller rainfall totals every few years, the general trend is increasing for heavy rain events.
In addition to the information from ClimateCentral, our National Weather Service station recently compiled some data from the past 30 years.
In the chart above, provided by the National Weather Service for Austin/San Antonio, the areas highlighted indicate that for Austin Mabry and Austin-Bergstrom, the annual rainfall increased over the past 30 years.
The number of days where both received greater than 1/10 of an inch of rain decreased. While at the same time, the number of days where both reporting locations received greater than 1/2 an inch and greater than an inch increased.
The data supports the information from ClimateCentral — we are getting more rain due to extreme rain events like we saw on Sunday. In other words, Austin’s wettest days are getting wetter.