Synoptic Intelligence™ Accuracy
How we validate our forecasts and what the numbers mean for your flight planning.
The Bottom Line
When Synoptic Intelligence™ says conditions will be flyable (VFR or Marginal VFR), it's correct 71% of the time. When it says conditions will be challenging(IFR or LIFR), it's correct 71% of the time. This gives you reliable advance notice to make or cancel plans.
Understanding Accuracy Metrics
We measure accuracy two ways because pilots make decisions differently than meteorologists:
Strict Category Accuracy: 41%
Did we predict the exact flight category (VFR, MVFR, IFR, or LIFR)?
This sounds low, but even official TAFs only achieve 50-60% at similar lead times. Weather is inherently uncertain days out.
Practical Accuracy: 71%
Did we correctly predict flyable (VFR + MVFR) vs challenging (IFR + LIFR)?
This is what matters for planning. You need to know: "Should I book the hotel or wait?" — not whether ceilings will be 2,500 ft vs 3,500 ft.
Accuracy by Lead Time
As expected, predictions are most accurate closer to departure and less certain further out:
Best performance — use for firm go/no-go
Slight degradation — good for planning
Still useful — for tentative planning
Key insight: Even at 72 hours, you're getting useful guidance that's better than random chance (50%) or persistence forecasting (~35%). This is the window where PlaneWX provides the most value — before TAFs exist.
Accuracy by Region
Some regions are more predictable than others. Here's how our tested regions performed:
Why the variation? Desert Southwest has stable, predictable weather. Great Lakes and Northeast have rapidly changing conditions — lake effect snow, frontal passages, and maritime influences make forecasting inherently harder. We're working on region-specific calibration to improve these areas.
What We've Learned
Our backtesting revealed a systematic pattern: Synoptic Intelligence™ tends to be slightly pessimistic about VFR probability. Here's what that means:
| When We Predict | Actual Result | What This Means |
|---|---|---|
| 30% VFR | ~55% VFR | Conditions often better than forecast |
| 50% VFR | ~75% VFR | Usually flyable despite "marginal" prediction |
| 70% VFR | ~80% VFR | Slightly better than forecast |
| 90% VFR | ~90% VFR | Well calibrated at high confidence |
This is actually good news. Pessimistic forecasting is safer than optimistic forecasting. You're more likely to be pleasantly surprised than disappointed. We're implementing calibration curves to make these predictions more accurate.
How We Tested
We performed rigorous backtesting using historical data from October 2025 through January 2026:
- Historical AFD Collection: We retrieved 90 days of archived Area Forecast Discussions from NWS Weather Forecast Offices
- Prediction Generation: Fed historical AFDs into our AI system (same model used in production) to generate VFR probability forecasts
- Verification: Compared predictions to actual METAR observations at 15 sample airports across 5 diverse regions
- Lead Time Analysis: Tested predictions at 24h, 48h, and 72h lead times
Test Dataset
How Does This Compare?
| Forecast Product | Category Accuracy | Useful Range |
|---|---|---|
| Official TAFs (0-6h) | 50-75% | 0-24 hours |
| Official TAFs (6-12h) | 45-60% | 0-24 hours |
| Synoptic Intelligence™ | 41% strict / 71% practical | 24-72 hours |
| Persistence ("same as now") | ~35% | Limited |
| Random Chance | 25% | None |
Key point: Synoptic Intelligence™ fills the gap between when TAFs end and when you need to make planning decisions. At 2-3 days out, there simply isn't a better publicly available aviation-specific forecast.
Continuous Improvement
We're actively working to improve forecast accuracy:
- Calibration curves — Correcting systematic biases based on backtesting data
- NBM integration — Blending National Blend of Models probabilistic forecasts
- Pattern learning — Building a library of recurring weather patterns and outcomes
- Region-specific tuning — Adjusting models for challenging areas like Great Lakes
- Expanded verification — Testing all 22 regions across full seasonal cycle
Important Disclaimer
Synoptic Intelligence™ provides weather information from federal regulatory agencies to support your flight planning. Our forecasts are intended to help you make earlier, better-informed decisions about trip planning. The pilot in command always makes the final go/no-go decision.
Our Commitment to Transparency
We believe pilots deserve to know how accurate our forecasts really are. That's why we publish this data openly. Weather forecasting is imperfect — especially days out — and we'd rather give you realistic expectations than overpromise. Our goal isn't to be perfect; it's to be useful for decision-making when you need it most.
Updated: January 2026