City vs city
Portola Valley vs San Diego, CA
Portola Valley and San Diego are tied on overall score, with the biggest factor difference in tornado.
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
Portola Valley: 22/100 · San Diego: 22/100
No gap.
Flood
Portola Valley: 28/100 · San Diego: 39/100
San Diego is 11 points higher.
Portola Valley: FEMA NFHL flood zones: 2 features intersect this tile.
San Diego: FEMA NFHL flood zones: 14 features intersect this tile.
Wind
Portola Valley: 2/100 · San Diego: 6/100
San Diego is 4 points higher.
Portola Valley: Wind exposure derived from ingested design wind / climatology tiles.
San Diego: Wind exposure derived from ingested design wind / climatology tiles.
Lightning
Portola Valley: 0/100 · San Diego: 1/100
San Diego is 1 points higher.
Portola Valley: Lightning exposure derived from ingested climatology tiles.
San Diego: Lightning exposure derived from ingested climatology tiles.
Tornado
Portola Valley: 0/100 · San Diego: 12/100
San Diego is 12 points higher.
Portola Valley: Tornado risk derived from NOAA SPC historical reports.
San Diego: Tornado risk derived from NOAA SPC historical reports.
Hail
Portola Valley: 1/100 · San Diego: 5/100
San Diego is 4 points higher.
Portola Valley: Hail risk derived from NOAA SPC historical reports.
San Diego: Hail risk derived from NOAA SPC historical reports.
Storm surge
Portola Valley: Unavailable · San Diego: Unavailable
A score difference cannot be calculated without both sources.
Portola Valley: Storm surge model is not available for this location yet.
San Diego: Storm surge model is not available for this location yet.
Wildfire
Portola Valley: 59/100 · San Diego: 69/100
San Diego is 10 points higher.
Portola Valley: Wildfire exposure derived from ingested fire potential tiles.
San Diego: Wildfire exposure derived from ingested fire potential tiles.
Ingested air quality
Portola Valley: 22/100 · San Diego: 24/100
San Diego is 2 points higher.
Portola Valley: 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 Diego: Air quality score derived from the latest ingested EPA AirNow AQI grid; may not reflect current conditions. See methodology for the recorded ingest date.