The SPC forecasts for meteorologists.
We forecast for you.
The Storm Prediction Center does exceptional work — for operational meteorologists. But millions of people in tornado-prone areas need a simpler answer: what is the probability a tornado affects my city today?
Clawd Front began in 2022 as an independent research project built entirely on open NOAA data. Six model versions later, it delivers calibrated metro-level tornado probabilities — a layer on top of official products, never a replacement for them.
Every input is public. Every output is verified against real NWS storm reports. The feature engineering and model weights are ours — everything else, you could build yourself.
Philosophy
Three principles we don't compromise on.
Open Data
Every input is public. NOAA, ECMWF, HRRR, SPC — anyone can download what goes in. We don't use proprietary data sources, and we never will.
Honest Numbers
When the model says 15%, it means 15%. Isotonic calibration is applied to every model version before it ships. Calibration is verified against held-out storm years, not just training data.
Verified, Always
Rolling AUC scored continuously against real NWS storm reports. If performance slips below 0.87 over any 90-day window, retraining triggers automatically. No manual intervention required.
Data Sources
What goes into the model and how often it updates.
| Source | What We Use It For | Update Frequency |
|---|---|---|
| NOAA HRRR | Atmospheric state features: CAPE, SRH, bulk shear, LCL, STP computed per grid cell | Hourly |
| ERA5 Reanalysis | Historical training data 2000–2013, pre-HRRR era backfill for model training | Monthly |
| SPC Storm Reports | Ground truth tornado events for model training and held-out verification | Daily |
| NWS LSRs | Local storm reports for calibration verification — real-world tornado occurrence data | Real-time |
| MRMS | Multi-Radar Multi-Sensor rotation tracks for Clawd Track nowcast layer | 2-minute |
| api.weather.gov | Live NWS warnings and watches for Clawd Track active alerts | 60-second |
@ClawdFront
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