Export Historical FEMA Disaster Data

A long historical declaration dataset can support policy and risk research, but only if collection limits and units of analysis are explicit. The FEMA Disaster Scraper exports the official summary records with stable IDs, dates, geographic codes, and declaration classifications.

Divide large exports into reproducible periods

Instead of requesting decades in one opaque run, collect documented intervals by state, incident class, or year range.

{"states":["PR"],"fromDate":"1953-01-01","toDate":"2025-12-31","maxResults":10000}

Record the input and run date with each file. Confirm that the result cap was not reached; if it was, split the interval and repeat. Upsert by OpenFEMA id when combining batches and retain last_refresh because historical records can be corrected.

Define the observation unit before analysis. Each row is a declaration-area summary. Counting unique disaster_number values estimates declared disasters, while counting rows estimates designated-area records. Neither count equals physical hazard occurrences, losses, or people affected.

Geographic boundaries and naming conventions change over decades. Prefer FIPS codes where applicable, but expect special area types and historical inconsistencies. Build a review table for unmatched geography rather than discarding it. Declaration types and assistance programs also reflect administrative policy that changes over time, so simple longitudinal comparisons need context.

Finally, cite OpenFEMA and keep official links in derived datasets. Historical declarations are valuable evidence of federal administrative action, but they should be combined with hazard, exposure, demographic, or loss sources only through a documented methodology.