SkyGround

County-level natural hazard risk data for researchers

All counties

Horry County, SC

Population: 348,574 · FIPS code: 45051

Relatively High Overall risk index: 98.2 / 100 (percentile among US counties)

Hazard breakdown

Hazard NRI rating NRI score NOAA events
(2016–2025)
Wildfire Relatively Moderate 89.9 0
Inland Flooding Relatively Moderate 92 72
Coastal Flooding Relatively High 87.6 0
Earthquake Relatively Moderate 95.9 —
Heat Wave Relatively Moderate 95 0
Tornado Relatively High 96.7 20

NOAA event counts are recorded county-level storm events from the NOAA Storm Events Database for 2016–2025. NOAA does not track earthquakes, and some hazard reports are filed by NWS forecast zone rather than county, so these counts are a partial, not exhaustive, record of recent activity. See the methodology page for details.

Federal disaster declaration history

Horry County has been included in 34 federal disaster declarations between 1989 and 2026, most recently for Winter Storm in 2026 (SEVERE WINTER STORM).

Source: FEMA OpenFEMA Disaster Declarations Summaries. Counts reflect county-level declaration records (a single disaster can produce more than one record per county), not modeled risk.

Geomagnetic latitude

Horry County sits at approximately 43.1°N geomagnetic latitude. Aurora is rarely visible this far from the geomagnetic poles, even during the most severe (G5) geomagnetic storms — though historic extreme storms have occasionally been seen at unusually low latitudes. See current space weather conditions for live geomagnetic activity and aurora forecasts.

Geomagnetic latitude is an approximate dipole-model calculation based on this county's geographic centroid (US Census Bureau). See the methodology page for details and limitations.

What these ratings mean

Each score reflects how Horry County's expected losses from that hazard compare to every other county in the country, based on FEMA's National Risk Index. A "Very High" rating means this county is among the most exposed in the US for that hazard relative to other counties — it does not mean a disaster is likely this year. See the methodology page for how these scores are calculated.