The Most Wildfire-Prone Zip Codes in America — USFS Data Analysis
The United States has more than 40,000 zip codes. Of those, several hundred face what fire scientists classify as extreme wildfire hazard — conditions where large fires are not a question of if but when. Using data from the USFS Fireshed Registry, the USGS, and two decades of fire occurrence records, we've identified the areas that consistently register the highest risk scores in our national dataset.
How We Identified the Most At-Risk Zip Codes
Our analysis draws on the Wildfire Risk to Communities platform, the national Fireshed Registry maintained by the US Forest Service, and the USFS Fire Occurrence Database, which records every wildfire of 1 acre or more since 2000. We then cross-referenced this with USGS topographic and land cover data to assess terrain-related risk amplifiers like slope, aspect, and canyon exposure.
The WildfireRiskScore (0–10) reflects a composite of these factors: historical fire frequency within 25 miles, the proportion of each zip code's land area classified as high or very high hazard by the Fireshed Registry, the presence of wildland-urban interface conditions, and terrain features that accelerate fire behavior. Scores of 8–10 represent the top percentile of risk nationally — areas where multiple severe risk factors converge.
California Dominates the High-Risk Rankings
California accounts for a disproportionate share of the highest-risk zip codes in the country. The combination of Mediterranean climate, extensive chaparral and mixed conifer forest, frequent drought, and offshore wind events creates the most consistently dangerous fire conditions in the continental United States.
Several factors distinguish California's highest-risk areas from other states. The chaparral ecosystem burns hot and fast, can recover enough fuel load to burn again within 15–20 years, and is highly susceptible to the "ladder fuels" problem when shrubs grow tall enough to carry fire into the tree canopy. Add the Santa Ana wind events — which can push sustained winds over 60 mph with humidity under 10% — and conditions for catastrophic fire runs are routine in autumn.
Southern California zip codes like 90210 (Beverly Hills) and 92101 (San Diego) register elevated scores because they border or sit within fire-prone hill and canyon terrain. But the highest scores in California tend to be found in the foothill and mountain communities of the Sierra Nevada foothills, the Santa Monica Mountains, and the Santa Cruz Mountains.
The 2018 Camp Fire — which destroyed Paradise, California — and the 2021 Dixie Fire, which burned more than 960,000 acres across multiple counties, are the most prominent examples of what very high risk scores translate to in practice. Both occurred in areas the Fireshed Registry had classified as extreme hazard for years before the fires.
Colorado: A Growing Threat on the Front Range
Colorado has emerged as one of the most significant wildfire risk states outside California. The December 2021 Marshall Fire — which burned through suburban communities in Boulder County in a grass fire driven by hurricane-force winds — was a wake-up call that the risk is not confined to mountain forests. It was the most destructive fire in Colorado history, destroying nearly 1,100 structures in densely populated suburban areas.
The Front Range corridor, which contains the bulk of Colorado's population, faces both mountain pine beetle kill — leaving millions of acres of dead lodgepole pine — and increasing grassland fire risk in the foothills and plains. Zip codes in the Denver metro area like 80203 score moderately, but communities in the foothills west of Denver and in the mountain towns above 7,000 feet regularly register scores in the 7–9 range.
Colorado's mountain communities have also experienced dramatic insurance market deterioration. Several counties in the foothills have seen insurers withdraw entirely, leaving homeowners with limited options at dramatically higher premiums.
The Pacific Northwest: Changing Fire Patterns
For decades, the Pacific Northwest was considered relatively protected from catastrophic wildfire by its wet marine climate. That picture has changed significantly. The 2020 Labor Day fires in Oregon and Washington burned over a million acres in a single weekend, killing dozens of people and destroying entire communities.
The fundamental driver is a warming climate that is extending drought seasons, reducing snowpack, and creating multi-week dry periods in a region whose forest ecosystems evolved under a much wetter summer regime. The 2021 heat dome event — which set all-time temperature records across Washington and Oregon — killed an estimated 1 billion marine invertebrates on the coast and pushed inland temperatures above 120°F in some locations, dramatically accelerating fire conditions.
Seattle proper, represented by zip codes like 98101, faces low direct wildfire risk given its urban density and maritime moisture. But the eastern slopes of the Cascades and the forests of the Olympic Peninsula now regularly register risk scores in the 6–8 range as summer fire conditions become more persistent.
Arizona and the Southwest: Desert Fire Goes Mainstream
The conventional wisdom that desert areas don't burn has been thoroughly overturned in the past decade. The spread of invasive annual grasses — particularly buffelgrass in the Sonoran Desert and cheatgrass across the Great Basin — has fundamentally changed fire behavior in ecosystems that historically burned rarely or not at all.
Phoenix-area zip codes like 85001 sit in what is increasingly a fire-active landscape. The Bighorn Fire of 2020 burned 120,000 acres in the Santa Catalina Mountains north of Tucson and threatened communities in its foothills. Arizona's ponderosa pine forests at middle elevations are particularly vulnerable — a century of fire suppression has allowed fuel loads to accumulate to levels that support fire behavior far beyond what those ecosystems historically experienced.
The 2022 Calf Canyon / Hermits Peak Fire in New Mexico became the largest in that state's recorded history at over 340,000 acres — started, ironically, by two prescribed fires that escaped containment. It burned through communities that had limited recent fire history, demonstrating that elevated risk scores can materialize rapidly when conditions align.
What the Data Shows About Risk Geography
Looking across our full dataset of zip codes, several geographic patterns are clear:
- Elevation transition zones — areas where low-elevation grassland or chaparral transitions to mid-elevation forest — consistently register the highest scores. These are the classic wildland-urban interface conditions.
- Canyon-adjacent areas score significantly higher than flat terrain with equivalent vegetation, because topography accelerates fire behavior and creates strong upslope drafts.
- Areas with drought-stress history — consistently high evapotranspiration deficit over 5+ years — show elevated scores that reflect both current fuel conditions and modeled future trajectory under continued warming.
- Proximity to previous large fires is a double-edged indicator. Areas that have burned recently may have reduced short-term fuel load, but those same areas are primed to burn again in 15–25 years as vegetation recovers.
The data also reveals a mismatch between perceived and actual risk. Some of the highest-scoring zip codes are in affluent communities where homeowners have historically had good access to insurance — a situation that is changing rapidly as insurers reprice and withdraw from the market.
Using Risk Scores for Real Decisions
The most important practical applications of wildfire risk data are in three areas: home purchase decisions, insurance procurement, and mitigation prioritization. A zip-code-level score gives you a useful first filter — if a zip code scores 7 or above, it warrants deeper due diligence before purchase, including an address-level assessment and contact with the local county fire department about specific property conditions.
For insurance, high risk scores are increasingly predictive of coverage availability and premium levels. Some California counties have begun requiring disclosure of wildfire risk scores as part of real estate transactions, similar to how flood zone status is disclosed. Several other states are moving toward similar requirements.
For mitigation, a high score doesn't mean a home is indefensible — it means that defensible space creation and home hardening are especially important. The USFS has documented that ember-resistant homes in the WUI have survival rates 2–3x higher than conventionally constructed homes during major fire events, even when those fires burn through surrounding vegetation completely.
Browse all zip codes in our database to check scores in your area, and use the data as the starting point for a deeper conversation with your local fire department, insurance agent, and county planning office about what you can actually do to reduce your exposure.