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Short alert with category and peak-tide time. Ideal if you're away from a screen.
Sign up for SMS →Puget Sound · Redondo Beach, WA
Community-run flood forecasts for Redondo Beach.
Software that reads NOAA tide predictions and five weather models, watching for the specific tide, pressure, wind, and surge conditions that flood Redondo Beach — and sends an alert when one's coming. Runs twice a day, year-round.
What this site does
A few times a year, a high tide stacks up with low pressure and onshore wind in a way that floods Redondo. It's rare enough that generic forecasts miss it and real enough to matter — the December 2022 event hit Category 5.
Twice a day, year-round, this site pulls NOAA tide predictions and five separate weather ensembles from the world's major forecast centers, compares them against every known Redondo flood event of the past five years, and returns a category from 1 to 7 for the next three days. If tonight looks like a Category 3 or higher, subscribers get a text or an email.
The system also checks itself. After each event it compares what it predicted to what actually happened — NOAA water-level observations, NWS alerts, local reports — and the classifier's accuracy is tracked over time. Current running score: 83% hit rate on real floods, 2% false-alarm rate on calm days.
A language model (OpenAI's o1 reasoning model) drafts the plain-language reasoning in each report — what tonight's setup looks like, which past flood it resembles, what to watch for. It does not predict the flood; that's the deterministic classifier's job. A second model reviews the reasoning for obvious mistakes before subscribers get a text. How we use it →
The 1–7 category reflects how severe an event is likely
to be. Cat 1–2 are ordinary high tides. Cat 3 is where we start
paying attention. Cat 5+ is December 2022 territory.
Not a substitute for official warnings. This is a
volunteer project and forecasts are best-effort. Always defer to
the National Weather Service and local emergency services for
flood watches, warnings, and evacuation guidance — see the
full disclaimer.
Three ways to subscribe
Delivery is free. Your number and email are stored only in a private subscriber list used to send alerts.
Email report
Full category reasoning: tide, pressure, wind, and comparison to past floods.
Sign up for email →Both channels
Text on any elevated forecast, plus the full email for reference.
Sign up for both →Next 72 hours
Predicted water levels for the next three days from NOAA's Tacoma reference station. The dashed line is the level at which we'd call it a Category 3.
Keep this running
Hosting, NOAA and weather API access, and SMS delivery add up. If these alerts have helped you or a neighbor, a small donation covers another month of operation.
Donations go entirely to operating costs. Nothing is personal — no one is paid to run this.
Secure checkout · US dollars