City vs city
Fort Thompson vs Gann Valley, SD
Fort Thompson currently scores 6 points higher overall than Gann Valley, with the largest gap 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
Fort Thompson: 31/100 · Gann Valley: 25/100
Fort Thompson is 6 points higher.
Flood
Fort Thompson: Unavailable · Gann Valley: Unavailable
A score difference cannot be calculated without both sources.
Fort Thompson: Flood model is not available for this location yet.
Gann Valley: Flood model is not available for this location yet.
Wind
Fort Thompson: 22/100 · Gann Valley: 22/100
No gap.
Fort Thompson: Wind exposure derived from ingested design wind / climatology tiles.
Gann Valley: Wind exposure derived from ingested design wind / climatology tiles.
Lightning
Fort Thompson: 27/100 · Gann Valley: 36/100
Gann Valley is 9 points higher.
Fort Thompson: Lightning exposure derived from ingested climatology tiles.
Gann Valley: Lightning exposure derived from ingested climatology tiles.
Tornado
Fort Thompson: 50/100 · Gann Valley: 12/100
Fort Thompson is 38 points higher.
Fort Thompson: Tornado risk derived from NOAA SPC historical reports.
Gann Valley: Tornado risk derived from NOAA SPC historical reports.
Hail
Fort Thompson: 41/100 · Gann Valley: 28/100
Fort Thompson is 13 points higher.
Fort Thompson: Hail risk derived from NOAA SPC historical reports.
Gann Valley: Hail risk derived from NOAA SPC historical reports.
Storm surge
Fort Thompson: Unavailable · Gann Valley: Unavailable
A score difference cannot be calculated without both sources.
Fort Thompson: Storm surge model is not available for this location yet.
Gann Valley: Storm surge model is not available for this location yet.
Wildfire
Fort Thompson: 54/100 · Gann Valley: 49/100
Fort Thompson is 5 points higher.
Fort Thompson: Wildfire exposure derived from ingested fire potential tiles.
Gann Valley: Wildfire exposure derived from ingested fire potential tiles.
Ingested air quality
Fort Thompson: 26/100 · Gann Valley: Unavailable
A score difference cannot be calculated without both sources.
Fort Thompson: Air quality score derived from the latest ingested EPA AirNow AQI grid; may not reflect current conditions. See methodology for the recorded ingest date.
Gann Valley: Air quality model is not available for this location yet.