City vs city
Half Moon Bay vs South San Francisco, CA
South San Francisco currently scores 5 points higher overall than Half Moon Bay, with the largest gap in wildfire.
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
Half Moon Bay: 16/100 · South San Francisco: 21/100
South San Francisco is 5 points higher.
Flood
Half Moon Bay: 47/100 · South San Francisco: 31/100
Half Moon Bay is 16 points higher.
Half Moon Bay: FEMA NFHL flood zones: 8 features intersect this tile.
South San Francisco: FEMA NFHL flood zones: 9 features intersect this tile.
Wind
Half Moon Bay: 1/100 · South San Francisco: 2/100
South San Francisco is 1 points higher.
Half Moon Bay: Wind exposure derived from ingested design wind / climatology tiles.
South San Francisco: Wind exposure derived from ingested design wind / climatology tiles.
Lightning
Half Moon Bay: 0/100 · South San Francisco: 0/100
No gap.
Half Moon Bay: Lightning exposure derived from ingested climatology tiles.
South San Francisco: Lightning exposure derived from ingested climatology tiles.
Tornado
Half Moon Bay: 4/100 · South San Francisco: 8/100
South San Francisco is 4 points higher.
Half Moon Bay: Tornado risk derived from NOAA SPC historical reports.
South San Francisco: Tornado risk derived from NOAA SPC historical reports.
Hail
Half Moon Bay: 8/100 · South San Francisco: 5/100
Half Moon Bay is 3 points higher.
Half Moon Bay: Hail risk derived from NOAA SPC historical reports.
South San Francisco: Hail risk derived from NOAA SPC historical reports.
Storm surge
Half Moon Bay: Unavailable · South San Francisco: Unavailable
A score difference cannot be calculated without both sources.
Half Moon Bay: Storm surge model is not available for this location yet.
South San Francisco: Storm surge model is not available for this location yet.
Wildfire
Half Moon Bay: 13/100 · South San Francisco: 54/100
South San Francisco is 41 points higher.
Half Moon Bay: Wildfire exposure derived from ingested fire potential tiles.
South San Francisco: Wildfire exposure derived from ingested fire potential tiles.
Ingested air quality
Half Moon Bay: 23/100 · South San Francisco: 25/100
South San Francisco is 2 points higher.
Half Moon Bay: Air quality score derived from the latest ingested EPA AirNow AQI grid; may not reflect current conditions. See methodology for the recorded ingest date.
South 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.