Hot, dry, and windy conditions that fuel the spread of wildfires are becoming increasingly common across much of the United States, according to a new analysis that highlights how climate change is transforming what was once a seasonal hazard into a near year-round threat in many regions.
Why it matters: The extension of what was traditionally considered “fire season” is placing significant strain on emergency responders, fire agencies, and land management operations already stretched by more frequent and intense wildfires.
According to a new report from the climate research group Climate Central, the number of days with heightened fire risk—known as “fire weather” days—has risen markedly over the past half-century. From 1973 to 2024, the Southwest has seen an average increase of 37 such days per year, while the West recorded an additional 21 days annually.
In regions like Texas, California, and New Mexico, that translates to roughly two more months of fire-favorable conditions each year compared to the early 1970s.
Zoom in: The trend isn’t limited to the West. Parts of the Northeast, including areas of New Jersey and Long Island, have also seen a noticeable uptick in fire-conducive conditions. Both regions recently grappled with significant wildfires, underscoring a broader national shift.
However, there are exceptions. A few regions—such as central North Dakota and northern Maine—have experienced a decline in fire weather days, according to the study.
How the data were analyzed: Climate Central’s findings draw on observations from 476 weather stations across the contiguous United States. The research breaks conditions down into 245 regional climate divisions and defines a “fire weather” day as one in which temperatures exceed 45°F to 55°F (seasonally adjusted), humidity levels fall near regionally specific thresholds, and sustained winds exceed 15 mph for at least two hours in a single day.
Key statistic: Human activity remains the leading cause of wildfires. Roughly 87% are ignited by people—whether from unattended campfires, sparks from utility lines, or other sources—according to the National Interagency Fire Center. Once a fire begins, fire weather conditions significantly increase the likelihood that it will spread quickly and unpredictably.
The broader picture: The frequency and severity of major wildfire events have more than doubled globally in the past two decades, according to a separate study. In the United States, this escalation is prompting states such as California and Idaho to brace for potentially explosive fire seasons, as hotter temperatures and stronger winds threaten to transform even minor sparks into large-scale blazes.
As fire weather becomes a more persistent feature of the American climate, the challenge of prevention and containment grows more urgent—demanding not just resources, but a long-term strategy for adaptation.
