City vs city
Alta Sierra vs San Francisco, CA
Alta Sierra currently scores 10 points higher overall than San Francisco, with the largest gap in ingested air quality.
Use this comparison for relocation decisions, insurance shopping, and hazard-prioritized mitigation planning.
Hazard breakdown
Scores describe each city’s reference grid tile, not every property. A missing model is unavailable, not zero risk. Air quality uses an ingested EPA AirNow snapshot and may not reflect current conditions; other factors describe baseline exposure. The overall score blends different hazards and is not a probability of damage. Read the scoring methodology and sources.
Overall
Alta Sierra: 35/100 · San Francisco: 25/100
Alta Sierra is 10 points higher.
Flood
Alta Sierra: 26/100 · San Francisco: 26/100
No gap.
Alta Sierra: FEMA NFHL flood zones: 1 features intersect this tile.
San Francisco: FEMA NFHL flood zones: 4 features intersect this tile.
Wind
Alta Sierra: 4/100 · San Francisco: 2/100
Alta Sierra is 2 points higher.
Alta Sierra: Wind exposure derived from ingested design wind / climatology tiles.
San Francisco: Wind exposure derived from ingested design wind / climatology tiles.
Lightning
Alta Sierra: 2/100 · San Francisco: 0/100
Alta Sierra is 2 points higher.
Alta Sierra: Lightning exposure derived from ingested climatology tiles.
San Francisco: Lightning exposure derived from ingested climatology tiles.
Tornado
Alta Sierra: 0/100 · San Francisco: 0/100
No gap.
Alta Sierra: Tornado risk derived from NOAA SPC historical reports.
San Francisco: Tornado risk derived from NOAA SPC historical reports.
Hail
Alta Sierra: 1/100 · San Francisco: 18/100
San Francisco is 17 points higher.
Alta Sierra: Hail risk derived from NOAA SPC historical reports.
San Francisco: Hail risk derived from NOAA SPC historical reports.
Storm surge
Alta Sierra: Unavailable · San Francisco: Unavailable
A score difference cannot be calculated without both sources.
Alta Sierra: Storm surge model is not available for this location yet.
San Francisco: Storm surge model is not available for this location yet.
Wildfire
Alta Sierra: 77/100 · San Francisco: 52/100
Alta Sierra is 25 points higher.
Alta Sierra: Wildfire exposure derived from ingested fire potential tiles.
San Francisco: Wildfire exposure derived from ingested fire potential tiles.
Ingested air quality
Alta Sierra: 100/100 · San Francisco: 25/100
Alta Sierra is 75 points higher.
Alta Sierra: Air quality score derived from the latest ingested EPA AirNow AQI grid; may not reflect current conditions. See methodology for the recorded ingest date.
San Francisco: Air quality score derived from the latest ingested EPA AirNow AQI grid; may not reflect current conditions. See methodology for the recorded ingest date.