Hazard Plain national table b1c_extent, release 2026-10 (as of 2026-09-30)
B1-c extent per county area and Storm Events series.
Files: b1c_extent.csv and b1c_extent.parquet (64,640 rows). The Parquet file carries this text as key-value metadata (keys hazard_plain.*).

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Columns: stcofips, prefix, series, series_label, level, scale_name, method, n_events, n_county_records, n_zone_records, first_year, last_year, n_with_measure, observed_min, observed_median, observed_max, unit, n_runs, n_damaging, worst_event_id, worst_date, worst_end_date, worst_value, worst_type, worst_level, worst_location, worst_text, worst_tie_dates, max_damage_event_id, max_damage_date, max_damage_usd, max_damage_text, worst_label, max_damage_label, max_damage_differs, applies_text, applies_member_keys, note_text

Sources:
  NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-30, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/
  NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-30, https://www.weather.gov/gis/ZoneCounty

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This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).