An extremely dry October is causing a sudden drought in almost half of the United States, sparking fires in the center-west of the country and hampering river transportation on the Mississippi River.
More than 100 different weather stations in 26 states, including Alaska, are recording their driest October on record, according to data from the Southern Regional Climate Center and the Midwest Regional Climate Center. Cities that have not recorded measurable rainfall in October include New York, Houston, Dallas, Philadelphia, San Francisco and Sioux City, Iowa, along with normally dry places like Los Angeles, Las Vegas and Phoenix, National Weather Service records show.
“We are on track to have a record dry October,” said Allison Santorelli, acting warning coordinator for the National Oceanic and Atmospheric Administration’s Weather Prediction Center in College Park, Maryland. This includes the Southeast, some areas of which experienced deadly flooding just the previous month from Hurricane Helene.
In June, less than 12% of the country was experiencing drought. It is now almost 50% and rising, according to the US Drought Monitor.
This fits the definition of “sudden drought,” which is different from dry periods that develop slowly, said Brad Rippey, a Department of Agriculture meteorologist and author of the drought monitor. A study last year showed that a warming world due to the burning of coal, oil and gas is causing more frequent and damaging flash droughts, such as one that hit the United States in 2012 at a cost of $30 billion and a devastating drought in 2022 in China.
For one-eighth of the area of the continental United States, no rain has been reported during the first 28 days of October. About 93% of the continental U.S. is seeing below-average rainfall in October, most with less than an inch, according to data from climate centers analyzed by The Associated Press.
Cities like Washington are forecast to reach 80 degrees Fahrenheit (27 degrees Celsius) on Halloween, just after Chicago and Detroit flirt with those summer temperatures. “That’s incredible” for the end of October, said meteorologist Ryan Maue, former NOAA chief scientist.
Santorelli said a high pressure dome has blocked moisture moving north from the Gulf of Mexico, keeping much of the United States dry from the Plains and the Midwest to the East Coast.
“We have been stuck in this lockdown pattern for almost two months,” Rippey said.
Studies over the past decade have shown that the jet stream—the air currents that move weather systems around the world—is wavier and gets stuck more often, attributing this to additional warming of the Arctic caused by anthropogenic climate change. Rippey said. What’s happening now, especially with an extremely warm Arctic and “febrile ocean temperatures in the North Pacific,” fits the theory well, said Jennifer Francis, a senior scientist at the Woodwell Climate Research Center, one of the pioneers of the concept.
Stagnant weather systems this year have caused disruption in places like Sioux City, where June rains caused so much water that they brought down a railroad bridge and forced people onto their roofs, said climatologist Melissa Widhalm, associate director of the Climate Center. Midwest Regional at Purdue University.
Asheville, North Carolina, which was devastated by Hurricane Helene, was inundated with nearly 14 inches (36 centimeters) of rain in three days in September, but has received just one-hundredth of an inch in October.
The Mississippi River, a major transporter of crops, is at such low levels that shipping loads must be restricted, Rippey said. It’s the third year in a row of problematic water levels in the river, he said. When Helene hit the Southeast and flooded North Carolina and Tennessee in late September, it provided a burst of fresh water that helped return Mississippi water levels to where they should be, but it didn’t last, Rippey said.
That can hurt the transportation of agricultural products, but fortunately for farmers, the sudden drought came after the corn and soybean harvest, Rippey said.
But dry fields mean a ripe situation for wildfires in both the Midwest and East, Rippey said. Farm equipment has started many fires accidentally, he said.
Five large uncontrolled fires on Tuesday burned more than 1,000 acres (404 hectares) in the East and Midwest, according to the National Interagency Fire Center.
Relief is expected for parts of the Midwest as western storm systems are forecast to bring rain, at times heavy, on Wednesday and Thursday, Santorelli said. But much of the East and Southeast will be dry for another week, he said.
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Mary Katherine Wildeman in Hartford and Michael Phillis in St. Louis contributed to this report.
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This story was translated from English by an AP editor with the help of a generative artificial intelligence tool.
