Why Flash Flooding Is Surging Across the U.S. This Summer

Flash flooding has surged across the United States this summer, with record-breaking rainfall events striking cities and small towns from Texas to New York City.

According to CNN, deadly floods began on July 4 in Texas, where slow-moving thunderstorms dropped more than an entire summer’s worth of rain in just hours, killing over 130 people. That same weekend, Tropical Storm Chantal drenched parts of central North Carolina, causing the Eno River to crest at record levels.

Illinois and New Mexico soon faced their own extreme events. Chicago saw a 1-in-1,000-year rainfall event, while storms in Ruidoso, New Mexico, swept away homes and left three people dead.

Why now? Meteorologists explain that summer is flash flood season. Warmer air holds more moisture, storms move more slowly, and urban surfaces like asphalt keep rainwater from soaking into the ground. Burn scars from past wildfires and drought conditions further amplify the risk, especially in places like Ruidoso.

Climate change is also a key factor. Warmer global temperatures allow the atmosphere to hold more water vapor, increasing rainfall intensity. Climate Central reports hourly rainfall rates have grown heavier in nearly 90% of large U.S. cities since 1970.

In Chicago, the average rainfall intensity has increased 8%—with this summer’s storms breaking records set decades ago.

The report emphasizes that much of the country’s infrastructure—roads, sewers, drainage systems—was not built to handle these kinds of events. As global temperatures rise, experts say more communities will face extreme rainfall in the years ahead.

Credit: CNN Newsource

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