SAN FRANCISCO — This week, 49 states are experiencing "moderate drought or worse," according to the U.S. government. That means more than 149 million Americans now live in a place affected by drought and that, thanks to a record-setting dry October, not enough rain has fallen on more than 318 million acres of farmland nationwide.
For those of us who live in the West, where we’ve become accustomed to water rationing and raging wildfires, the fast-accelerating drought is an all-too-familiar scenario.
With a historic number of wildfires burning in New Jersey and reservoir levels plummeting, Gov. Phil Murphy declared a drought warning for the state on Wednesday despite the fact that some much-needed rain did fall recently.
"Now I know we were relieved to see a few drops of rain on the weekend. The truth is that rainfall was nowhere near enough. And unfortunately, these unseasonably dry conditions will not be ending anytime soon," Murphy told reporters about the declaration, which allows water suppliers to divert the precious resource to the hardest impacted parts of the state.
With other states grappling with similar conditions, does the worsening drought mean that your tap will soon run dry? No, but the longer it persists, the bigger the impact on daily life will be. Here’s what you should know.
What is a drought?
The National Oceanic and Atmospheric Administration defines drought as "a deficiency in precipitation over an extended period, usually a season or more, resulting in a water shortage causing adverse impacts on vegetation, animals, and/or people. It is a normal, recurrent feature of climate that occurs in virtually all climate zones, from very wet to very dry."
In California, we have two real seasons: dry and wet. It doesn’t rain much, if at all, from May through September. But from October through April, residents can usually count on several precipitation events that turn hillsides green and refill reservoirs. But in some periods, such as what was experienced between 2020-2022 or from 2011-2017, lower wet season rainfall totals result in drought conditions in the state and across much of the West.
Why is so much of the U.S. now experiencing drought conditions?
October was the driest month on record "for nearly 80 climate stations across much of the eastern half of the country," according to NOAA. Those places typically see ample amounts of rain in that month.
“A number of locations saw over 30 days without any measurable rainfall, which is fairly rare in the East,” NOAA says on its website. “Measurable means at least 0.01 inches of rain. Philadelphia has had a record 39 consecutive days of no rain through November 6, 2024, and the count continues to grow while the city awaits measurable rain. Columbia, South Carolina, went 38 days without measurable rain, a streak that just ended on November 4, 2024, marking their third-longest streak on record. Atlanta, Georgia, only received a trace of rain, which is a far cry from their October average of 3.28 inches.”
What role does climate change play?
Droughts, as NOAA notes, are a normal part of life on Earth. That said, rising global temperatures are also playing an increasingly big role in their frequency and severity.
Under what is known as the Clausius-Clapeyron equation, for every degree Celsius of temperature rise the atmosphere holds 7% more moisture. That dramatically increases the chances for extreme precipitation events, but it also means that, due to increased evaporation rates, the risk of droughts also rises.
That helps explain why parts of North Carolina that were decimated by heavy rainfall from Hurricane Helene in late September are now experiencing abnormally dry conditions or moderate drought little more than a month later.
"When it rains, it's increasingly likely to pour, just because of basic thermodynamics, and when it's not raining, when it's sunny and hot — and, of course, increasingly hot due to climate change — it's going to be easier to evaporate that water back into the atmosphere, leading to more arid conditions during that period, more rapidly intensifying droughts," UCLA climate scientist Daniel Swain told Yahoo News last year.
Could cloud seeding break the drought?
Some states across the arid West use a process called “cloud seeding” to try to increase precipitation, especially in mountainous regions.
"Cloud seeding is a weather modification technique that improves a cloud's ability to produce rain or snow by introducing tiny ice nuclei into certain types of subfreezing clouds," the Desert Research Institute in Nevada states on its website. "These nuclei provide a base for snowflakes to form. After cloud seeding takes place, the newly formed snowflakes quickly grow and fall from the clouds back to the surface of the Earth, increasing snowpack and streamflow."
Those efforts can increase precipitation by 5%-10% in some locations, but they rely on specific topography and weather conditions.
“During dry winters when storm systems are absent for long periods, cloud seeding cannot occur, because cloud seeding requires the presence of moisture-filled clouds,” DRI says on its website.
In other words, the government hasn't yet figured out how to control the weather and cloud seeding isn't a solution for drought conditions spanning several states.
Get used to 'whiplash weather'
Living in the drought-plagued West has taught residents to expect the unexpected. Drought has threatened sources of water like the Colorado River for several years running only to give way to winters filled with extreme rainfall. Depending on how much rain falls in the rainy season, water restrictions in California are enacted and rescinded, and wildfire risk rises and falls.
In 2023, when a series of atmospheric river storms battered California following three years of extreme drought, Gov. Gavin Newsom summed up the dizzying change of fortunes in a message posted to social media.
“Megadroughts. Wildfires. Historic floods and atmospheric rivers. This whiplash weather is not an anomaly. California is proof that the climate crisis is real and we have to take it seriously,” Newsom wrote.