A spate of flash flooding emergencies in the United States over the past two weeks has highlighted the dangerous aspects of July. The month saw multiple once-in-a-millennium rainfall events across the United States, but July isn’t over yet.
A flash flood emergency is the highest level of flood warning, with more than a dozen issued across the country so far this month. This puts July 2026 within reach of a monthly record of such alerts.
A once-in-a-millennium flood hit the Texas Hill Country from July 15th to 17th. In some areas, nearly a year’s worth of rain fell in just a few days, sending deadly waves of water into rivers and streams. The probability of such a flood occurring each year is 0.1%. But it was the second year in a row that it has hit this part of central Texas.
This is just one of several flash flood emergencies recently issued across the country. There have been 15 flash flood emergencies in the past two weeks. West Virginia experienced record flooding Tuesday night. Utah remains in the scars of wildfires on Sunday. A once-in-a-millennium rainstorm in Missouri forced campers to be rescued from cabin roofs and trees a week before Texas.
According to the National Weather Service, flash flood emergencies are rare situations that typically occur when extremely heavy rain poses a serious threat to human life and catastrophic damage has already occurred or is expected to occur imminently. However, as the world warms, extreme rainfall events are becoming more common.
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An analysis released in April by the nonprofit research organization Climate Central found that of the 144 U.S. cities studied, 90% saw an increase in hourly precipitation intensity between 1970 and 2025. In the 129 cities where the increase occurred, hourly precipitation was on average 15% higher than it was a few decades ago, and every region of the country saw an increase.
The cause of these trends is anthropogenic climate change. For every degree Fahrenheit increase in temperature, the air contains 4% more water vapor. And since 1970, the U.S. has warmed by nearly 3 degrees Celsius on average, resulting in a significant increase in the amount of water vapor available during heavy rains, Climate Central found. Warming of the oceans also leads to an increase in water vapor in the atmosphere.
Storms will take advantage of this added moisture and ultimately produce more precipitation, an impact that has long been predicted in national climate assessments. Now we are seeing those predictions come true with devastating effects on the ground.
The number of flash flood emergencies issued in the United States this year continues to rise, reaching 32 as of July 21. This year, nearly half of the 2026 flood emergencies were issued in July alone, although that’s short of the 49 emergencies in 2025 and 38 similar warnings in 2024 at this point in the year. And many of them were devastating.
2024 was the record holder for the most flash flood emergencies in a year, with 93 such warnings. Last year, there were 55 cases, the second highest on record. 2026 is behind the previous record annual pace, but if this summer’s flooding continues, it could quickly catch up.
Flooding reached historic levels in parts of Upshur County, West Virginia, Tuesday afternoon and evening after more than 5 inches of rain fell in about six hours. The National Weather Service called the event “an especially dangerous situation.”
One stream gauge in the flood zone peaked at more than 10.6 feet Tuesday night, breaking the previous record of 8.3 feet set during a devastating flood in 1985. It was the first time in nearly 80 years of record-keeping that the water gauge had reached major flood stage.
And more flash flood emergencies could occur before the end of the month as moisture from Tropical Storm Vata interacts with a stationary cold front in the southern Mid-Atlantic and Carolinas, dumping up to a month’s worth of rain starting Wednesday and into the weekend.
Some severe flash floods avoided the “emergency” label but still caused damage and disruption.
New York, for example, endured weather whiplash on July 18 as the city reeled from a heat wave and smoke pollution from Canadian wildfires and flash flooding from slow-moving thunderstorms that dumped several inches of rain in a short period of time. Water flooded subway stations and left cars stranded on city streets.
A flash flood warning was then issued for New York City and neighboring states as thunderstorms then swept through the area Tuesday afternoon and evening.
Flash floods are becoming increasingly common and severe in the Big Apple because the city’s infrastructure is not designed for the increased rainfall of a warming world. For example, in 2021, flooding from the remnants of Hurricane Ida killed 13 people, some of whom were trapped in their basements.
New York is not the only city suffering, as existing stormwater infrastructure was built for a climate that no longer exists. But the city illustrates the challenges many other urban areas face.
New York’s stormwater system can only handle up to 1.75 inches of rainfall per hour, but this is being exceeded more frequently. The 2021 Ida wreck dumped more than 3 inches of rain in just one hour, setting records and causing stormwater systems to back up into basements, subway tunnels, sewers and storm drains, turning roads into rivers.
Even considering the shift to more frequent and intense downpours, July this year was unusual in terms of devastating floods that affected various parts of the country. And there are no signs of a long drought coming.
But due to climate change, this July’s flash floods, and the pace of flash floods of the past two years, could just become the new normal for midsummer.
