English · Español

Live: https://sismo-alerta-235ca.web.app/?lang=en · Built with Claude: it started as a Claude Dashboard, and Claude wrote the code, the tests and the deployment setup.

Earthquake tracking and alerts for Panama and the region, with the estimated intensity where you are, a map of recent earthquakes and a simulation of the P and S waves traveling from the epicenter. It started with the M7.7 earthquake of October 9, 2026 and its aftershocks.

Important: this is not an early warning. Agencies publish each earthquake minutes after it happens; for a nearby quake, the shaking arrives before the notice. It's for knowing right away what it was, how big, how it affected you, and for following the aftershocks. In a strong earthquake, follow the instructions of SINAPROC, Panama's civil protection agency.

EMSC (IGC, UNA, EMSC…)  ──WebSocket──┐
EMSC FDSN (every 30 s)  ─────────────┼──► Cloud Run "sismo-ingestor" ──► Firestore  events/{id}
USGS (every 30 s)  ──────────────────┘        │  merges solutions of the same quake
                                              │  estimates the intensity at each phone
                                              └─► FCM ──► Flutter app (notification)
Flutter app ──► Firestore devices/{uid}: token, location (~1 km), threshold, local adjustment

The page and the app use the Atkinson, Worden & Wald (2014) intensity prediction equation, with magnitude and hypocentral distance, plus a configurable local adjustment.

For the M7.7 earthquake of October 9, 2026, the model matches what people reported to USGS "Did You Feel It?" in Chitré (6.5) and Santiago (6.2). In Panama City, though, the model gives 4.6 against 5.1 reported (169 reports), so the local adjustment defaults to +0.6 there. The same formula lives in backend/app/intensity.py, app/lib/core/intensity.dart and web/js/intensity.js, each tested against those data.

Waves are animated with average crustal speeds: P at 6.0 km/s and S at 3.5 km/s.

A static site with no build step (index.html, js/, css/, with d3 and Leaflet vendored in vendor/):

• On load: it asks EMSC for the catalog since the mainshock, in pages of 300 events.
• Live: it connects to the EMSC WebSocket and adds each new earthquake seconds after it's published.
• Fallback: it polls the catalog every 2 minutes in case the connection drops.

It also reads the USGS "Did You Feel It?" reports and official aftershock forecast for the mainshock (SEQUENCE.usgsEventId), and lets you download the table as CSV, with a link to each earthquake's EMSC page. Colors follow a palette checked for color blindness, with separate steps for light and dark mode: one color per day of the sequence, red for the mainshock, gray for the week before, and the USGS ShakeMap intensity scale.

Filters above the map choose the period (week before, all, today, last 24 h, last 6 h) the minimum magnitude (M3+, M4+, M5+) and the area: the original aftershock zone, the whole region, or whatever the map shows (useful as the sequence moves). The area decides which earthquakes count everywhere on the page, figures included. Period and magnitude apply to the map, the timeline, the intensity chart, the table and the CSV; the figures at the top and the rate charts always count the whole sequence. Filters go in the address too, so a link like ?periodo=24h&mag=4&area=region opens that view.

The frequency chart shows, every hour, the earthquakes per hour over the previous 6 hours (all and M4+, on a log scale), with their mean magnitude and mean estimated intensity at the reference place in aligned panels below.

To follow a different earthquake, change SEQUENCE in web/js/config.js.

The page is in Spanish and English. It follows the browser's language, and the ES/EN button at the top switches and remembers it. To share a link in one language, add ?lang=en or ?lang=es. All text lives in web/js/i18n.js.

Run locally

cd web
npm run serve            # http://localhost:8080
npm install && npm test && npm run e2e   # tests; e2e uses fixed data from October 9

Publish to Firebase Hosting (once)

npm install -g firebase-tools
firebase login
firebase deploy --only hosting --project your-project    # from the repo root

It goes live at https://your-project.web.app.

Automatic deploy (optional). Every push to main that touches web/ is published, once two repository settings exist on GitHub:

• Variable FIREBASE_PROJECT_ID: your project id.
• Secret FIREBASE_SERVICE_ACCOUNT: the JSON key of a service account with the Firebase Hosting Admin role.

Costs. A first visit downloads about 120 KB compressed (d3 is trimmed to the modules the page uses: web/tools/build-d3.sh); later visits only revalidate the page's own files, a few KB.

• Free plan (Spark): 360 MB a day, about 3,000 first visits. Check it in the Firebase console under Hosting → Usage. Past the limit, the site stops being served until the next day.
• Blaze plan: extra transfer costs US$0.15/GB, about 2 cents per 1,000 visits. If you share the link publicly, use Blaze with a budget alert (the app backend needs it too).

Visit statistics (optional). Paste the Google Analytics 4 measurement ID (G-…) into ANALYTICS.measurementId in web/js/config.js. Advertising features are off, the footer says so, and the page records which filters, language and reference place people use. Without an ID nothing is loaded.

Limits

• Load on EMSC. Each visitor queries EMSC directly, which is fine for hundreds of people. If the link goes viral, the page should read from a file the app backend updates instead.
• Maps. With no setup the map uses OpenStreetMap's tiles, which are fine for light use. For public use, get a free CARTO key at https://carto.com/basemaps/apikey (non-commercial: 5 million tiles a month) and paste it into TILES.cartoKey in web/js/config.js.

1. Project: create a Firebase project (or add Firebase to a Google Cloud one).
2. Firestore: create it in native mode, in the region you prefer (for example us-east1).
3. Authentication: under Authentication → Sign-in method, turn on Anonymous.
4. iPhone notifications: upload your APNs key under Project settings → Cloud Messaging.

PROJECT_ID=your-project REGION=us-east1 ./infra/deploy.sh
gcloud run services logs read sismo-ingestor --project your-project --region us-east1 --limit 50

To try it locally without touching anything: cd backend && DRY_RUN=true python -m app.main, then open localhost:8080/status.

Cost: the service needs one always-on instance (1 vCPU, 512 MiB) to keep the WebSocket open. At Cloud Run prices that's about US$40–45 a month after the free tier; check it in the Google Cloud pricing calculator.

To pay less:

• Poll every 30 s without the WebSocket: set POLL_SECONDS=30 and drop the WebSocket. Cloud Run still needs an active instance.
• An e2-micro VM: runs the same container and falls within the Compute Engine free tier in some U.S. regions.

You need stable Flutter, Xcode for iOS and Android Studio for Android.

cd app
python3 tool/setup_platforms.py      # creates android/ and ios/ with permissions and settings
dart pub global activate flutterfire_cli
flutterfire configure --project=your-project   # replaces lib/firebase_options.dart
flutter run

On iOS, open ios/Runner.xcworkspace and add the Push Notifications and Background Modes → Remote notifications capabilities.

• Minutes of delay. IGC and EMSC publish 3 to 10 minutes after the quake. A warning that arrives before the shaking needs dedicated sensors or an official system.
• Location while the app is open. GPS location updates when the app opens and while it's open. To get alerts with the app closed, set a fixed location (home or office) in Settings.
• The model is an average. Real intensity varies by one degree or more with the ground, the building and the floor.
• OpenStreetMap tiles. The app uses the public tiles, which are fine for personal use. If it grows, it should move to its own tile provider.

• Earthquakes: EMSC Seismic Portal, which brings together the Institute of Geosciences of the University of Panama (IGC), the National University of Costa Rica (UNA), USGS (NEIC) and EMSC.
• "Did You Feel It?" reports and the aftershock forecast: USGS.
• Map: © OpenStreetMap contributors.

MIT © 2026 Noel Moreno Lemus