Disaster History
Wildfire in America
How fires start, why some of them run, and what a century and a half of the record has taught us about living at the edge of fuel.
The Hazard
Three things decide what a fire does: fuel, weather, and terrain.
A wildfire is combustion moving across a landscape. What it does after ignition depends on three variables working together: the fuel available to burn, the weather acting on that fuel, and the shape of the ground underneath. Change any one and the same spark produces a different outcome.
Fuel is the part people can see. Grass, brush, needle litter, standing timber and the built material of houses all carry fire, but they carry it at different speeds. Fine fuels like cured grass ignite in seconds and spread fast; heavy timber ignites slowly and burns long. Most of what burns each year was lit by people: the USDA Forest Service puts the human-caused share of reported wildfires at 85% to 97%.[2] What matters most is fuel moisture, and fuel moisture is set by weeks of weather rather than by the day of the fire.
Weather supplies the two things that turn a small fire into a large one. Low relative humidity dries fine fuels until they ignite from almost anything. Wind then pushes the flame front, tilts it into unburned fuel ahead, and carries burning material downwind. The U.S. Fire Administration notes that embers lofted by a fire can be deposited several miles ahead of the flame front[10], which is why structures can ignite well before any visible fire arrives.
Terrain is the quietest of the three and the most consistently underestimated. Fire moves faster uphill because rising heat preheats the fuel above it, and canyons and narrow drainages can channel wind and behave like chimneys. A slope does not need to be dramatic to change a fire's speed.
None of these three variables is confined to a season or a region. The Marshall Fire burned through suburban Boulder County on December 30, 2021, in cured grass, during a windstorm, with no forest involved.[9] Fuel, weather and terrain lined up, and the calendar was not consulted.
The Fire Danger Rating Scale
Low
Fuels do not ignite readily from small firebrands. Lightning or sustained heat can still start a fire. Fires that do start creep, smolder, and spread slowly.
Moderate
Fires can start from most accidental causes, though the number of starts stays low. Grass burns briskly on windy days. Timber fires spread slowly to moderately, and control is generally straightforward.
High
All fine dead fuels ignite readily and fires start easily from most causes. Spread is rapid and short-distance spotting is common. A fire can become serious without a prompt and successful first attack.
Very High
Fires start easily from all causes and spread rapidly right after ignition. Spot fires are a constant danger, with long-distance spotting and fire whirls possible in heavier fuels.
Extreme
Fires start quickly, spread furiously, and burn intensely. Direct attack is rarely possible except immediately after ignition. Crews work the flanks until weather or fuels change.
How the rating is set
The National Fire Danger Rating System calculates these five levels from fuel moisture, fuel type, and weather observations.[12] A rating describes the condition of the landscape, not a forecast that a fire will occur. Two places at the same rating can behave very differently once terrain and wind are added, which is why the rating is a planning input for agencies rather than a prediction for any one property.
Risk Geography
Fire follows fuel and wind, not state lines.
The West burns the most acreage in most years. That is a fact about terrain and dry season length, not a statement that other regions are safe. Fire counts run high across the Southeast every year, the southern Plains carry fast grass fires, and some of the most destructive recent events happened in places nobody filed under fire country.
The Interior West and California
California, Oregon, Idaho, Nevada, Montana
Long rainless summers, steep terrain, and heavy accumulated fuel produce the largest acreage totals in most years. Offshore wind events, the Santa Ana in southern California and the Diablo in the north, arrive at the driest point of the year and drive the fires that reach communities. A century of fire exclusion left many of these forests carrying far more fuel than they did historically.
The Southeast
Florida, Georgia, the Carolinas, Texas
The Southeast records some of the highest fire counts in the country every year, most of them small and quickly controlled. Prescribed burning is far more established here than in the West, which keeps fuel loads lower. Drought years change that arithmetic quickly, and the region's dense wildland-urban interface means a fire that does escape has houses close at hand.
Grassland and the Front Range
Colorado, Kansas, Oklahoma, Nebraska
Cured grass carries fire faster than timber does, and grass fires are driven almost entirely by wind. The Marshall Fire moved through suburban Boulder County on December 30, 2021, during a windstorm the National Weather Service recorded gusting to 115 mph. It destroyed 1,084 homes and seven commercial structures.[9] There was no forest involved.
10.1M
Acres burned nationally in 2020, the largest single year from 2020 through 2025
National Interagency Fire Center[1]
2.7M
Acres burned in 2023, the smallest year in that same six-year span
National Interagency Fire Center[1]
1,200+
Lives lost at Peshtigo, Wisconsin in 1871, still the deadliest U.S. wildfire
NOAA National Weather Service[5]
What History Shows
The record keeps making the same point: the wind decides, and the houses are the fuel.
The deadliest wildfire in American history happened in Wisconsin. On October 8, 1871, after an unusually dry summer, fire swept through Peshtigo and sixteen surrounding towns, burning between 1.2 and 1.5 million acres and claiming more than 1,200 lives.[5] It burned the same night as the Great Chicago Fire and was almost entirely overshadowed by it. Nearly every element of the modern pattern is already visible: dry fuels, high wind, land clearing as the ignition source, and no warning system of any kind.
Four decades later the fires of 1910 rewrote federal policy. More than three million acres burned across Idaho, Montana and Washington, most of it during the "Big Blowup" of August 20 and 21, and at least 85 people died.[6] The young Forest Service emerged from that season committed to eliminating fire from the landscape, a suppression doctrine that held for more than half a century. It succeeded at stopping small fires, and in doing so it allowed fuel to accumulate in forests that had historically burned often and lightly. Much of the fuel load the West carries today was assembled by that decision.
The modern lesson arrived in the suburbs. In October 1991 the Tunnel Fire burned about 1,600 acres in the Oakland and Berkeley hills and killed 25 people, destroying thousands of homes and apartments in an area of narrow roads and dense housing.[11] The acreage was small. The loss was not, because once enough structures stand close together, the structures themselves become the fuel bed and the fire stops behaving like a forest fire.
Two recent events show how little time that arithmetic leaves. The Camp Fire ignited near Pulga, California on November 8, 2018 and burned into Concow, Paradise and Magalia. Over 18 days it covered 153,336 acres, destroyed or damaged more than 19,000 structures, and caused 85 civilian deaths.[7] NIST's investigation focused less on the flames than on the evacuation: how notification reached people, how traffic moved, and where residents sheltered when the roads failed. On August 8, 2023, wind-driven fire destroyed more than 2,200 structures in Lahaina, Hawaii and killed more than one hundred people.[8]
Read together, the record is unusually consistent. The events that kill people are wind events, not fuel events. The warning problem is almost always a communications problem rather than a detection problem. And the households that come through best are the ones that decided in advance where they would go, because a fire moving in wind does not leave time to make that decision well. What follows a fire is its own long project, covered in our guides to displacement, insurance cancellation, and recovery after a disaster.
Detection and Response
The warning arrives before the fire, if you know what to listen for.
Unlike a tornado, wildfire risk is forecast days ahead. The weather that makes a bad fire possible is predictable even though the ignition is not, and the alerts are issued on the weather rather than on any specific fire.
Fire Weather Watch
A Fire Weather Watch is issued when conditions that support dangerous fire behavior are expected to develop, typically 12 to 24 hours ahead.[3] It is the planning window. It is when agencies pre-position crews and when a household that has been meaning to sort out its documents and its route has a day to do it.
Red Flag Warning
A Red Flag Warning means those conditions are occurring or imminent, normally issued within 12 hours of the event.[3] Thresholds are set regionally because fuels differ by region. One representative set requires sustained winds above 15 mph, relative humidity below 25%, and ten-hour dead fuel moisture below 9%, all at the same time.[4] A warning does not mean a fire exists. It means that if one starts, conditions favor rapid spread and short work of a first attack.
Who responds, and how it scales
Initial attack is local. Most starts are worked by the nearest engine or crew and never make the news, which is why the annual fire count runs so far ahead of the number of fires anyone can name. When a fire outgrows local capacity it escalates through a national mobilization system coordinated by the National Interagency Coordination Center, which assigns incident management teams and moves crews, aircraft and equipment between geographic areas.[13]
The National Weather Service supports this directly. Incident meteorologists deploy to large fires and issue spot forecasts for the specific terrain a crew is working, because a general regional forecast is too coarse to predict what wind will do in one drainage.
The gap the record keeps showing
Detection has improved steadily. Notification has not kept pace. The investigations that followed the Camp Fire and the Lahaina fire both gave close attention to notification. How residents were told to leave, how road capacity held up, and what happened to people who never received an alert. Those are local questions with local answers, which is the argument for knowing your own community's alert system and your own second route out before a warning is issued.
What You Can Do
From the record to your own address.
History is useful here because the variables repeat. The work that matters gets done during a Fire Weather Watch, or well before one. Know how your county issues alerts. Know two ways out. Understand how the building you live in would handle an ember fall, whether you own it or rent. Our wildfire preparedness guide covers each of those in order.
Landmark Events
Four fires that changed policy, science, or both.
October 8, 1871 · Northeast Wisconsin
The Peshtigo Fire
The deadliest wildfire in United States history. Fire moved through Peshtigo and sixteen other towns after a dry summer, burning 1.2 to 1.5 million acres. It burned the same night as the Great Chicago Fire and was largely forgotten as a result. No warning system existed, and land clearing supplied the ignition.
Case study coming soon
August 20-21, 1910 · Idaho, Montana, Washington
The Big Burn
More than three million acres burned in two days, killing at least 85 people. The season shaped American fire policy more than any other event: the Forest Service adopted an aggressive suppression doctrine that lasted over half a century. The fuel accumulation that decision produced is still being managed today.
Case study coming soon
November 8-25, 2018 · Butte County, California
The Camp Fire
153,336 acres over 18 days, more than 19,000 structures destroyed or damaged, and 85 civilian deaths. NIST's multi-year investigation reconstructed the fire progression timeline and studied notification, evacuation traffic, and temporary refuge areas. It became the reference case for how a wildland fire behaves once it enters a dense residential community.
Read the full case studyAugust 8, 2023 · Lahaina, Maui, Hawaii
The Lahaina Fire
A wind-driven fire destroyed more than 2,200 structures and killed more than one hundred people, with damage estimated near $5.5 billion. Multiple official reviews followed, examining warning, communications and evacuation. The event moved wind-driven fire in non-forest fuels onto the national agenda in a way earlier fires had not.
Read the full case studyThe Archive
Wildfire history, state by state.
State profiles document the major events, the policy changes that followed, and the current risk picture for wildfire-affected states.
Highest acreage: the West and Great Basin
California
Coming soon
Oregon
Coming soon
Washington
Coming soon
Idaho
Coming soon
Montana
Coming soon
Nevada
Coming soon
Arizona
Coming soon
New Mexico
Coming soon
Utah
Coming soon
Colorado
Coming soon
Wyoming
Coming soon
Alaska
Coming soon
High fire counts: the Southeast and southern Plains
Texas
Coming soon
Oklahoma
Coming soon
Kansas
Coming soon
Florida
Coming soon
Georgia
Coming soon
North Carolina
Coming soon
Significant events outside the traditional fire regions
Hawaii
Coming soon
Wisconsin
Coming soon
Minnesota
Coming soon
Michigan
Coming soon
Tennessee
Coming soon
New Jersey
Coming soon
Sources
Citations
- [1] National Interagency Fire Center. "Wildfires and Acres." NIFC Fire Information Statistics. Accessed September 2, 2026. [source]
- [2] USDA Forest Service. "Wildfires: When Fun Turns to Flames." Accessed September 2, 2026. [source]
- [3] NOAA National Weather Service, New York NY. "Fire Weather Watch and Red Flag Warning." Accessed September 2, 2026. [source]
- [4] NOAA National Weather Service, St. Louis MO. "Red Flag Warning and Elevated Fire Danger Criteria." Accessed September 2, 2026. [source]
- [5] NOAA National Weather Service, Green Bay WI. "The Peshtigo Fire." Accessed September 2, 2026. [source]
- [6] Forest History Society. "The 1910 Fires." U.S. Forest Service history collection. Accessed September 2, 2026. [source]
- [7] National Institute of Standards and Technology. "NIST Investigation of the 2018 Camp Fire." Accessed September 2, 2026. [source]
- [8] U.S. Fire Administration, FEMA. "Preliminary After-Action Report: 2023 Maui Wildfire." Accessed September 2, 2026. [source]
- [9] NOAA National Weather Service, Boulder CO. "High Winds and Marshall Fire on December 30th, 2021." Accessed September 2, 2026. [source]
- [10] U.S. Fire Administration, FEMA. "Protecting structures from wildfire embers and fire exposures." Accessed September 2, 2026. [source]
- [11] California Governor's Office of Emergency Services. "Fires in the Oakland Berkeley Hills History." Accessed September 2, 2026. [source]
- [12] Wildland Fire Application Information Portal. "Adjective Fire Danger Ratings." Accessed September 2, 2026. [source]
- [13] National Interagency Fire Center. "National Fire News." National Interagency Coordination Center situation reporting. Accessed September 2, 2026. [source]