More Frequent Fire Weather

The analysis reveals a significant increase in fire weather days across much of the contiguous U.S., with the western U.S. experiencing far more frequent fire weather than the east. While the western U.S. has seen strong increases, particularly in the Southwest during spring and summer, parts of the eastern U.S. have also seen impactful increases, especially in the Southeast and Northeast. The study emphasizes that while human activity causes 87% of wildfires, fire weather primes the landscape for these fires to ignite and spread.

• The western U.S. experiences significantly more fire weather than the eastern U.S., averaging 31 fire weather days annually compared to 8 days in the east.
• Since 1973, the western U.S. has seen a strong increase in annual fire weather days, with some areas in Southern California, New Mexico, Texas, and Arizona experiencing an increase of approximately two months per year. Some locations in California, Nevada, New Mexico, and Texas now see fire weather twice as often as in the early 1970s.
• Seasonal increases in fire weather are most prominent during spring across much of the country. In the western U.S., the Southwest has seen the largest jumps in spring and summer, with parts of New Mexico, Arizona, and Colorado gaining about a month of fire weather in spring, and Southern California, Utah, and Arizona gaining about three weeks in summer.
• In the eastern U.S., while many areas saw only a few additional days of fire weather since 1973, the Northeast and Southeast have experienced the greatest increases. Specifically, northern New Jersey and coastal New York have seen at least 10 additional days annually, and the northern Piedmont area in North Carolina has seen nearly two additional weeks.
• Human activity was responsible for 87% of U.S. wildfires from 2001 to 2024, accounting for nearly half of all burned acres, though fire weather conditions (temperature, relative humidity, and wind) are what prime the landscape for these fires to spread.

APA

Climate Central (2025). More Frequent Fire Weather. https://www.climatecentral.org/climate-matters/more-frequent-fire-weather

Chicago

Climate Central. More Frequent Fire Weather. 2025. https://www.climatecentral.org/climate-matters/more-frequent-fire-weather.

Wikipedia

{{cite report |author=Climate Central |title=More Frequent Fire Weather |date=7 May 2025 |url=https://www.climatecentral.org/climate-matters/more-frequent-fire-weather |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climatecentral2025more, author = {{Climate Central}}, title = {{More Frequent Fire Weather}}, institution = {Climate Central}, year = {2025}, month = may, url = {https://www.climatecentral.org/climate-matters/more-frequent-fire-weather}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }