How extreme was the recent San Jacinto River rainfall?

Earlier this month, persistent and intense rainfall to the northeast of Houston caused severe flooding on the San Jacinto River, affecting thousands of residents. Our sincere best wishes are with everyone affected!

As we look to risk assessment, it’s important to determine how extreme this rainfall really was. Yuchen Lu, a third-year PhD student, compared the rainfall at different durations to Atlas 14 estimates of rainfall probability, finding that this was a 10 to 25-year event depending on how it’s analyzed. This underscores the importance of vulnerability reduction and flood preparedness.

You can find Yuchen’s more detailed analysis here or the source code on GitHub.

As we look to managing future flood risks, further improvements to risk assessment are needed. Atlas 14 estimates are useful but do not account for the increasing likelihood of extreme weather. More fundamentally, probability distributions of annual maximum rainfall at a single point are completely silent on the spatial or temporal structure of rainfall, which can matter for flood impacts. We are working hard to address both of these limitations in our research – stay tuned for more updates!