Floods & Storms

What's the flood risk where you live?

Enter a street address for a precise answer, a ZIP code for the whole area, or use your current location — to see your FEMA flood zone on a map, whether proposed maps change it, your ZIP's flood history, and what to do next.

Nothing you type is saved. Address suggestions and street addresses go through our server to OpenStreetMap and the U.S. Census Bureau only to find the location. "Use my current location" asks your browser's permission first; the coordinates go through our server to OpenStreetMap only to name the nearest address. Only the location (never an address) is then sent to FEMA, NOAA and the Census Bureau. Shared links include only the ZIP code.

About this data and its limits

  • Flood zones come from FEMA's National Flood Hazard Layer — the official, effective flood maps. A zone describes the mapped chance of flooding, not a guarantee either way.
  • A ZIP code isn't a map area. We use the Census Bureau's ZIP Code Tabulation Area, which approximates it; PO-box-only ZIPs have none. Most ZIPs contain several zones, so only a street address gives one answer.
  • Addresses are placed by the Census Geocoder, which estimates a spot along the block, or by OpenStreetMap when the Census can't match them. Your current location comes from your device and can be off by tens of meters or more indoors. Near a zone line, confirm on FEMA's official map.
  • "Has my zone changed?" compares the effective map with FEMA's preliminary and pending maps. FEMA has no preliminary maps for Houston yet: Harris County's MAAPnext drafts aren't published as open data, so we link to them instead of reading them.
  • Flood history counts FEMA's anonymized flood-insurance claims by ZIP — only insured losses appear, so real flooding was more widespread.
  • Insurance information is educational only — not insurance or legal advice.

Official sources