Wildfire risk in Sierra County varies a lot by location. The overall scores run from 26.4 in Sierraville to 82.7 near Loyalton, with a county midpoint of 61.4.
We scored 154 points across Sierra County on the same 0–100 scale a Satelife address report uses, and they do not land in one place. 6% of them come out Very High, while 10% are Moderate. Which end your own parcel sits at is not something a county map can tell you.
FEMA NRI also rates Sierra County: all-hazards risk Very Low · social vulnerability Relatively High · community resilience Relatively Low · annualised wildfire frequency 0.0154.
Sources: FEMA National Risk Index 1.20.0 (Dec 2025), county record · USFS Wildfire Risk to Communities v2.0, mean of the grid cells inside the county. Both describe the county as a whole, never an address in it.
What does your Sierra County address score?
A county range shows the spread. Your parcel sits somewhere inside it — the report says where, and what to do about it.
Free to request · PDF report with a 0–100 score, the drivers behind it, and a mitigation plan
Most of the places we scored fall in the High tier. High has 128 points, compared with 16 in Moderate and 10 in Very High; none fell in Low.
FEMA’s National Risk Index rates Sierra County’s wildfire risk as Relatively Moderate, and its wildfire expected annual loss as Relatively Moderate. FEMA also rates the county’s all-hazards risk as Very Low, with social vulnerability Relatively High and community resilience Relatively Low.
Since 1984, Sierra County has had 59 recorded fire perimeters, and 135,782 acres have burned. That equals 22.2% of the county.
The largest fire listed is Cottonwood (1994), at 48,111 acres.
The most recent large fire is Bear (2024), at 3,323 acres. Another fire in the list, Elephant (2026), burned 13,930 acres and was partly in Sierra County.
Fire perimeters coloured by decade. Select a perimeter for its name, year and size.
Perimeter sources: NIFC Interagency Fire Perimeter History · WFIGS Interagency Perimeters · largest on record: Cottonwood 1994. Perimeters are simplified for display; acreage is the figure the source records.
For local context, Loyalton (population 740) has a median wildfire risk score of 64.6. The county’s highest single scored location is also near Loyalton.
Downieville (61.4) and Sierra City (60.6) are close to each other and close to the county midpoint.
Sierraville comes in lower at 56.5, and it also includes some of the county’s lowest scored locations.
The score is the median of the sampled points nearest that community — a community-scale indicator, not a score for any individual property in it. Population comes from the community's own record where the source carries one.
Terrain contributes to risk, but it varies in a tighter band than other factors in Sierra County. Terrain scores run from 55.0 near Sierraville to 65.0 near Downieville.
Vegetation and fuels vary more: 40.0 in Sierraville up to 80.0 near Loyalton, with a midpoint of 70.0.
Fire weather was not measured for Sierra County. What is measured includes hazard-zone scores, which are high in many locations, with a midpoint of 88.2.
Past-fire-pattern scores also vary widely, from 5.0 near Downieville to 95.0 near Loyalton.
Fire weather was not measured at the sampled points in Sierra County. The other four indicators on this page were, and the bars below show what they found.
Risk is not uniform across the county. The highest scored location is near Loyalton at 82.7, while the lowest is in Sierraville at 26.4.
Among named communities, Loyalton has the highest median score at 64.6. Downieville and Sierra City are close behind at 61.4 and 60.6.
Sierraville’s community median is 56.5, which is lower than the other listed communities but still within the county’s broader High-leaning pattern.
Each bar is what one part of the score covers across Sierra County, on the same 0–100 scale. A long bar is a part of the risk that depends on where you are; a short one is the same almost everywhere.
The tick on each bar is the middle value. Tier boundaries — Moderate at 25, High at 50, Very High at 75 — are the faint lines behind them.
| Layer | Min | Median | Max | Lowest place | Highest place | Points |
|---|---|---|---|---|---|---|
| Terrain | 55 | 55 | 65 | near Sierraville | near Downieville | 154 |
| Vegetation & fuels | 40 | 70 | 80 | Sierraville | near Loyalton | 154 |
| Hazard zone | 10 | 88.2 | 93.8 | Sierraville | near Downieville | 154 |
| Fire history | 5 | 20 | 95 | near Downieville | near Loyalton | 154 |
| Composite | 26.4 | 61.4 | 82.7 | Sierraville | near Loyalton | 154 |
Independently of Satelife's layers, the USFS Wildfire Risk to Communities grid puts the county's mean annual burn probability at 1.48% (90th percentile cell: 2.99%), with a mean conditional flame length of 11.23 ft. 98% of the 25,697 grid cells inside the county carry burnable fuel at all.
Source: USFS Wildfire Risk to Communities v2.0 (ImageServer, county extent).
CAL FIRE has no mapped Fire Hazard Severity Zone at 95 of the 154 sampled points — the zones cover Local Responsibility Areas, and most of this county is state or federal land. At 95 of them the USFS grid above supplied the hazard reading instead.
154 sample points on a ~2.3 km grid, plus one at the centre of each community, weighted with the Satelife county profile v1 · median layer coverage 90%. Scores are 0–100 and comparable within the county, not across states.
For a property conversation, countywide patterns and the exact location both matter. In this county, most scored points are in the High tier, with smaller pockets in Very High and Moderate.
The USFS Wildfire Risk to Communities product shows a mean annual burn probability of 1.48%, and a 90th-percentile cell value of 2.99%.
That same USFS product indicates 98.3% of the county is in cells that can burn, with a mean conditional flame length of 11.23 feet.
Find out where your Sierra County parcel sits
Slope, the fuel touching the structure, the road out, the fire history within a mile — measured at your address, not averaged across the county.
Free to request · PDF report with a 0–100 score, the drivers behind it, and a mitigation plan
Every one of the 20 ZIP areas that touch Sierra County — we run address-level reports in all of them. They are grouped by the median score of the points we sampled inside each, which is a neighbourhood-scale indicator and not a score for any property: two homes in the same ZIP routinely land in different tiers.
Very High 2 ZIPs
High 9 ZIPs
No sampled point inside 9 ZIPs
89511 · 95959 Downieville · 95981 Downieville · 96103 Sierra City · 96106 Sierra City · 96109 Loyalton · 96129 Loyalton · 96135 Loyalton · 96161 Sierraville
Grouped from 11 of 20 ZIP areas — the rest had no sample point fall inside them. The community shown is the nearest mapped place to the ZIP's centre.
ZIP areas are Census 2020 ZIP Code Tabulation Areas intersecting the county boundary.
Since 1984, 135,782 acres have burned within 59 mapped fire perimeters. That is 22.2% of the county.
The largest listed fire is Cottonwood (1994) at 48,111 acres. The most recent large fire is Bear (2024) at 3,323 acres.
No. Scores range from 26.4 in Sierraville to 82.7 near Loyalton. Community medians also differ, from 56.5 in Sierraville to 64.6 in Loyalton.
No. Fire weather was not measured for Sierra County.
FEMA’s National Risk Index rates Sierra County’s wildfire risk as Relatively Moderate, and its wildfire expected annual loss as Relatively Moderate.
A county range shows the spread. An address-level Satelife report shows where in that spread your property actually sits — PDF, per-layer score, and a prioritized mitigation plan.
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