October 2024 brought record-setting drought to the U.S., with dry conditions covering more than half the country.
A strong high-pressure system kept temperatures warm and rainfall scarce, driving rapid flash droughts in multiple states. Scientists note this trend has been accelerated by climate change, making drought monitoring more challenging.
Record Drought Conditions in October 2024
In October 2024, unusually dry conditions swept across more than half of the contiguous United States. By October 29, abnormal dryness and drought were impacting over 78 percent of the American population—the highest level recorded in the 25-year history of the U.S. Drought Monitor.
Much of the country experienced both drier and warmer weather than normal, largely due to a strong high-pressure ridge that remained stalled high in the atmosphere for weeks. According to the Southeast Regional Climate Center, 100 weather stations across the U.S. recorded no rain during October, with cities like Philadelphia, Atlanta, Birmingham, Dallas, Las Vegas, and Sacramento among those reporting zero precipitation. Over 70 weather stations documented their driest October on record.
Drought Map Shows Intensified Conditions
The map above from the U.S. Drought Monitor shows drought conditions across the contiguous U.S. as of October 29, 2024. The Drought Monitor, a partnership among the U.S. Department of Agriculture, NOAA, and the University of Nebraska-Lincoln, depicts drought intensity in shades ranging from yellow to red. The map is based on comprehensive data, including climate, soil, crop, and water conditions gathered from over 350 federal, state, and local observers across the country. NASA also contributes important measurements and models to support this drought monitoring effort.
Drought had expanded from covering just 12 percent of the country in June to 54 percent as of October 29. The rapid development created what NOAA describes as a “flash drought” in many parts of the country. Flash droughts are typically brought on by lower-than-normal rates of precipitation, accompanied by abnormally high temperatures, wind, or radiation.
“Although droughts usually develop slowly over the course of months and years, a flash drought rapidly intensifies over the course of a few weeks to a couple of months,” said Caily Schwartz, a scientist at the Global Water Security Center at the University of Alabama. Schwartz noted that in Nebraska, where the National Drought Mitigation Center is located, there has been little rain and higher-than-normal temperatures in October. Much of the state was in severe drought (represented as orange in the map) in late October.
Nationwide Warmth Contributes to Drought Spread
Almost the entire country was warmer than normal the week of October 23-29, and drought was present in every state except Alaska and Kentucky. The High Plains and South were the warmest regions, with temperatures 10 to 12 degrees Fahrenheit (6 to 7 degrees Celsius) above normal.
Even in the Southeast where Hurricane Helene dropped significant precipitation in late September, many places dried out rapidly, with some recording zero precipitation since the hurricane.
“This fall has been a prime example of flash drought across parts of the U.S.,” said Jason Otkin, a meteorologist at the University of Wisconsin-Madison. “These events can take people by surprise because you can quickly go from being drought-free to having severe drought conditions.”
Otkin co-authored research published in Science that showed that droughts have intensified more rapidly since the 1950s due to human-caused climate change. According to the research team, flash droughts have become more common over much of the world, making drought monitoring and forecasting more difficult.
NASA Earth Observatory image by Michala Garrison, using data from the United States Drought Monitor at the University of Nebraska-Lincoln.
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2 Comments
FLASH! “Flash drought” is yet another scary, made-up word-pair to scare the public. We already have “ocean acidification, more acidic, global heating, and tipping point,” all poor descriptions of what they are allegedly describing, but using pejorative words to appeal to one’s emotions rather than their prefrontal lobe. A drought doesn’t happen quickly, like a deluge or wall of water resulting from the rain, nor does it happen overnight like a severe frost. A drought is something that happens over a period of weeks as soils slowly dry out and plants and humans lower the water table. There is very little about it that is ‘flashy!’
“By October 29, abnormal dryness and drought were impacting over 78 percent of the American population—the highest level recorded in the 25-year history of the U.S. Drought Monitor.”
While the US Drought Monitor was officially instituted in 1999, temperature and precipitation measurements go back much farther than that. Twenty-five years doesn’t even meet the usual definition of climate. Droughts, which can last hundreds of years, play an important role in the survival of societies. Indeed, archaeologists and paleontologists attempt to reconstruct droughts from thousands of years ago to understand the impact on human societies and the animal populations. However, the severity is at least as important as the areal extent and duration. The official Drought Index is primarily for the current use of farmers, commodity traders, and insurance companies. To understand the climatological issue, one needs more than a 25-year index.