Accuracy and reliance
We work hard to make every forecast as accurate as we can — pulling NOAA tide data, combining five major weather ensembles, and comparing conditions to every documented Redondo flood of the past several years. The system is scored against what actually happened after every event, and the running hit rate and false-alarm rate are tracked openly on the how-it-works page and in the flood reports archive.
Even so, flood forecasting is inherently uncertain. Tide, pressure, wind, and surge interact in ways even the best models can’t always capture. A low-category forecast can be followed by flooding. A high-category forecast can pass with no visible impact. The self-audit numbers reflect this honestly, but they are averages over past runs — they do not predict whether any specific future forecast will be correct.
Not a replacement for official sources
Do not use this site as your sole source of flood information. Always defer to:
- National Weather Service — Seattle at weather.gov/sew for active watches, warnings, and special weather statements.
- King County Office of Emergency Management for evacuation, shelter, road closures, and coordinated local guidance.
- City of Des Moines emergency services — 9-1-1 for emergencies; the City’s non-emergency public-safety line for other event-time information.
Government agencies have legal authority, real-time sensor networks, and direct coordination with first responders that a volunteer software project does not.
At your own risk
You use this site, its forecasts, its alerts, and its archived reports at your own risk. Redondo Beach Flood Watch, its operator, contributors, and hosting providers disclaim all warranties, express or implied, including but not limited to fitness for a particular purpose and accuracy of the information provided. No party associated with this project shall be liable for any decision, action, or inaction taken based on information provided here.
If this forecast disagrees with an official NWS watch, warning, or statement, follow the official guidance. If conditions on the ground are worse than this forecast suggests, act accordingly — the system cannot see what’s happening outside your window, and you can.
When in doubt
- Move vehicles and valuables away from low-lying shoreline areas.
- Monitor NWS Seattle for updates.
- Call 9-1-1 for life-threatening conditions. Don’t wait for a forecast to confirm what you can see.
Report issues
If you notice an error — a tide prediction that doesn’t match NOAA, a report citing a flood that didn’t happen, a missed event — please contact the operator so we can update the self-audit and tune the classifier. Every correction makes the system more reliable.
Last revised: April 2026.